
Book >C/^ 



SMITHSONIAN DEPOSIT 



/ 



TESTIMONIALS. 



From Rev. James Greeu, an experienced and most successful Teacher. 

I believe the introduction of Scientific and Practical Agriculture into our 
academies and high schools, as a regular branch of study, to be highly de- 
sirable. I am confident, too, that it would be highly popular, both with 
our farmers and their sons. As soon as a suitable text-book can be pro- 
cured, I wish to introduce the subject into my own course of instruction. 

From what I know personally of Professor Campbell, from what I have 
witnessed of his examinations of classes in agricultural science ; and from 
the general plan of his work on this subject, I have no doubt that it will 
meet the wants of teachers, and fill a vacancy now existing in our series of 
test-books. JAMES GREER, 

Prin. Brownsburg High-school, at Brownsburg, Rockbridge Co., Va. 

April 2d, 1859. 

From J. R. Jones, Esq., a?i eminent Lawyer and Agriculturalist of Brunswick 

County. 
■"eofessor J. L. Campbell. 

Dear Sir, — I am gratified to hear that your " Manual" is now ready for 
the publisher. In every eifort to bring the great principles of Chemistry, 
Geology, and Physiology, to the clear and easy comprehension of practical 
and intelligent agriculturalists, I feel a very decided interest ; and the world 
of farmers will hail him as a great public benefactor who successfully ac- 
complishes that object. 

That portion of your manuscript which was submitted to me, as chairman 
of the Committee on Essuys at the last State Agricultui-al Fair, met my 
cordial approval ; and, so far as I am competent to judge of a work which 
treats of scientific subjects, of which I can claim but a very limited know- 
ledge, gave promise of success in your design. 

It is proper to state, in this connection, that your work was withdrawn 
from the committee, at my suggestion, that you might retain the copyright, 
which would have been forfeited, if it had obtained a premium from the 
Virginia State Agricultural Society. 

I will be obliged, if you will order five copies of your Manual to be sent 

to my address, care of Messrs. Mcllwaine, Son & Co., Petersburg, Va., as 

soon as it is issued from the press. 

I am, very truly and respectfully, yours, 

J. EAVENSCROFT JONES. 
(2) 



TESTIMONIALS. 

From Major Wm. Giliiam, rmfessor of Clifmisfri/ and Agricullure in the 
Virginia Military Institute. 

Virginia Military Institcte, 1 ,, , 10 i lom 
\ March iZth, 1859. 
Lexington, Va., J 

Professor J. L. Campbell. 

Dear Sir, — I have very carefully read the manuscript of your work upon 
Scientific and Practical Agriculture, and it gives me great pleasure to say 
that I think it eminently suited to the purposes for which it was intended. 

I have long felt that just such a work, combining, as it does, a complete 
outline of the principles of science which have a direct bearing upon agri- 
culture, together with full directions for the management and improvement 
of the soil ; the cultivation of the crops peculiar to our country ; their rela- 
tive value; the rotation of crops, &c. &c., was very much needed. I rejoice 
to see that you have succeeded so well, and have adapted your work — the 
first of its kind in our country — to meet the peculiar wants of the agricul- 
turalists of the South and West. Yours, very sincerely, 

WILLIAM GILHAM. 



The following is from some of (he Author s former pupils, most of whom are sons 

of farmers. 

Having attended Prof. Campbell's highly interesting and instructive Lec- 
tures on Scientific Agriculture, we were most favorably impressed with the 
author's accurate scientific attainments, which, combined with a practical 
knowledge of the subject, such as few possess, eminently qualify him for fur- 
nishing a work of rare excellence, both for the scientific and practical 
agriculturalist. 

ISAAC P. IIEISKELL, WM. T. WALKER, 

W. Y. CHESTER, GEORGE LIFE, 

JOHN D. BROOKS, J. W. M'COWN, 

GEO. G. JUNKIN, J. M'D. M'CLUNG, 

JAMES S. GREENLEE, HARVEY GILMORE, 

H. T. DARNALL, WM. F. WILHELM, 

WM. A. M'CUE, D. D. PENDLETON, 

WM. M. WILLSON, JAMES HAYNES, 

GEO. L. LEYBURN, M. H. HOUSTON, 



A MANUAL 



SCIENTIFIC AND PRACTICAL 



AGRICULTURE, 



THE SCHOOL AND THE FARM. 



J.^Lt>"CAMPBELL, A.M 

PnOFESSOR OP PHYSICAL SCIENCE, WASHINGTON COLLEGE, VA. 



Happy tho man, who studying Nature's laws, 
TUrough known effects can trace the secret cause. 

DrydEiN's Vmcit. 



PHILADELPHIA : 

LINDSAY & BLAKISTOK. 

1859. 



Entered, according to Act of Congress, in the year 1859, liy 

LINDSAY & BLAKISTON, 

in the Clerk's Office of the District Court of the United States for the Eastern 

District of Pennsylvania. 

STEREOTTPED BY J. FAGAN PKINTED BY C. 6HEKMAN & SON. 






J^Mtittioi);. 



To the many young gentlemen whom I have had 
the honor and the pleasure of instructing in this 
important department of Applied Science, this little 
"Work is affectionately dedicated, as a token of the 
interest still felt in their success in life. 

The Authoe. 



(xi) 



PREFACE. 



There is a rapidly increasing demand for scien- 
tific information, reduced to such a form that it 
may be applied to the daily business of Agriculture. 
This makes the adoption of the study of Agricul- 
ture into our higher schools a matter of great im- 
portance. It has already led to the introduction of 
the subject into several of our best colleges, and into 
a few of the higher schools ; but those teachers who 
have undertaken the important task of giving to our 
farmers' sons, that kind of scientific training, which 
especially fits them for the intelligent pursuit of their 
future calling, have felt the want of a text-book of 
thQ right kind. One of the leading objects which 
the Author of this little work has kept in view, has 
been to meet this want, as far as possible. 

Another demand for some such work, comes from 
those already engaged in the cultivation of the soil. 
2 (xiii) 



PREFACE, 



It comes from those who have been long employed as 
"tillers of the land," as well as from the younger 
farmers, who desire to improve upon the old system 
(or rather want of system) of culture, which has 
worn out so many of our best lands. It is hoped 
that this demand, also, will be met, to some extent, 
at least, by what is here offered to the agricultural 
public. 

Hence, the great purpose kept in view has been 
the preparation of a "Manual" adapted to the School 
and the Farm, to serve especially as a guide to the 
youthful mind in acquiring such knowledge and men- 
tal training as might lay a firm foundation for future 
and higher attainments. 

The only systeraatie books on this subject hereto- 
fore available, have been either foreign works, or 
compilations from these, modified to suit limited sec- 
tions of our country. Not one of them is at all 
adapted to the agriculture of our Southern and 
Western States. It is true that the leading princi- 
ples of science, as applied to the culture of the soil, 
are the same everywhere ; but the 2Jractical applica- 
tion of these principles is as widely difierent in differ- 
ent latitudes, as the numerous crops cultivated in the 
several sections of our wide-spread country. Their 
application to Southern Agriculture has been gene- 



PREFACE. XV 

rally left out of view, in all books of a general char- 
acter hitherto issued on this great subject. This little 
work will, therefore, come in competition with no 
other of like character. Some excellent productions, 
on specific subjects in Agriculture, have appeared 
from the pens of Southern writers, and will be found 
alluded to in the text, where they have been made 
available by the writer. But this is designed to fill 
a place before unoccupied. 

The following general plan has been pursued : — 

1, A few preliminary definitions are given as an 
"Introduction." 

2. The agencies, "Heat, Light, and Electricity," 
have such of their general laws discussed as are 
necessarily connected with other subjects afterwards 
introduced, and especially with reference to the rela- 
tions they bear to Agriculture and domestic afiairs. 

3, The language of chemistry, so far as is neces- 
sary to a clear understanding of the subject, is briefly 
summed up and explained in the form of " Symbols 
and Nomenclature." 

4. The most important elementary substances, 
both "Metalloids and Metals," with such of their 
inorganic compounds as are of interest to the agri- 



XVI PREFACE. 

culturalist, are described, and their properties illus- 
trated by simple experiments. 

5. The leading principles of "Organic Chemistry" 
are concisely stated, and applied to the discussion of 
both "Vegetable and Animal" compounds. 

6. The sources from which plants derive their 
nourishment are described. 

7. Then, to show clearly the relation of the plant 
to its sources of nourishment, and to show what con- 
ditions are necessary for healthful and vigorous 
growth, the various organs of plants, and the func- 
tions they perform are given, under a general outline 
of "Vegetable Physiology." 

8. The "Soil," as the only source of plant nourish- 
ment under our control, is then discussed, with refer- 
ence, /rsi, to its "Geological Origin" — showing how 
the quality of soils is influenced by the rocks from 
which they are formed ; secondly, with reference to 
its " Mechanical Management" — embracing the prin- 
ciples involved in "Plowing, Draining, etc.," with 
their practical application ; thirdly, with reference to 
its "Chemical Treatment" — showing what is neces- 
sary to fertility in a soil, and what constitutes any 
substance a good fertilizer. 



PREFACE XVU 

9. "Special Manures" — their composition and che- 
mical relations to one another, and to the soil and 
crop, with the principles which should govern their 
"Application," are treated somewhat definitely. 

10. The "Selection of Seed," and the leading prin- 
ciples to be observed in "Planting and Culture," are 
briefly discussed. These principles are then cvpi^lied 
to the planting and culture of "Indian Corn," 
"Wheat," "Clover and Grasses," "The Southern 
Pea," "Tobacco," and "Cotton." 

11. The principles, with a few examples of "Ptota- 
tion of "Crops," are stated. 

12. The "Value of different Crops, as Articles of 
Food," is briefly given. 

13. Then, to show the relation between the animal 
and his food and habits, we have a brief outline of 
that part of "Animal Physiology" which is most in- 
timately related to the rearing, feeding, and general 
management of stock, followed by practical applica- 
tions. 

In every part of the work, the Author has endea- 
vored to blend principles and practice — first in a 
general way, then more specifically, as applied to 
particular cases in every-day exjierience. 



XVni . PREFACE. 

The reader must not suppose that this, or any other 
book alone, can make him a good farmer. Books, 
without practice, can no more make successful farm- 
ers, than they can make successful lawyers or physi- 
cians. The judgment must be exercised by close 
observation, and by varied experience, in farming as 
well as in other pursuits. 

The experience of others must be consulted, too, 
and carefully weighed. To do this, every farmer 
who expects to be intelligent in his profession, must 
secure the regular reading of some good Agricultural 
Journal, and such Essays as are from time to time 
presented before Agricultural Societies. Fortunately 
for our young farmers, many of our best agricultural 
writers are among the most successful cultivators of 
the soil. The results of their experience may be 
made familiar, by spending an occasional leisure hour 
with such papers in hand, as tell us what they have 
been doing, and how they have succeeded. But do 
not, by any means, try every man's experiments. 
Study this little book carefully, and it will aid you to 
decide on the probable value of any given operations. 
Examine into the causes and effects involved in what 
has been done, and you may see at once whether the 
experimenter has understood his own operations or 
not. 



PREFACE. XIX 

What is here offered is the result of the Author's 
labors of several years, in giving instruction to 
young men on the important topics discussed. The 
matter, of course, is not all original. It has been 
gathered up from various sources — partly from books, 
partly from Agricultural Journals and Essays, partly 
from observation, and partly from a limited practical 
experience. The Author is not an entire stranger to 
the plow-handle and the hoe, and therefore claims a 
higher position than that of mere "book-farmer." 

The experiments given for illustration are very 
simple, and may be performed by any ingenious 
youth, or by the teacher of almost any respectable 
school. The apparatus and chemicals required to 
begin with, can be bought for ten or twelve dollars. 
A list of them will be found in the Appendix. 

Prof. LuDWiG, of Lexington, deserves many thanks 
for valuable and friendly assistance in drawing some 
of the principal cuts given, and in copying several 
others. My young friend and pupil, H. T. Darnall, 
is the delineator of the cut in Chapter XV, which 
illustrates so clearly the system of side-hill irrigation 
there given. To my friend and neighbor. Prof. Gil- 
ham, of the Virginia Military Institute, I am under 
peculiar obligation for the labor he has undergone, in 
revising the whole of my manuscript, and in making 



PREFACE. 



some most valuable suggestions, which have been 
adopted, and which have done much to give clearness 
and precision to several of my scientific discussions. 

My indebtedness to various books and journals has 
been generally acknowledged in the body of the 
work. 

It is due the engravers, Messrs, Baxter & Harley, 
to add, that they deserve high commendation for 
their faithfulness in executing the various cuts with 
which the work is illustrated. The Frontispiece, 
especially, presents a rare specimen of artistic skill. 



J. L. CAMPBELL. 



Washington College, > 
Lexiugton, Va., June, 1859. j 



TABLE OF CONTENTS. 



CHAPTER I. 
Preliminary Definitions and Illustrations page 25 

CHAPTER II. 
Heat, Light, and Electricity , 29 

CHAPTER III. 
Chemical Symbols, Equivalents, and Nomenclature 49 

CHAPTER IV. 
History and Properties of the Metalloids 55 

CHAPTER V. 
History and Properties of the Metals 77 

CHAPTER VI. 
Organic Chemistry — Chemistry of Plants 98 

(xxi) 



• 



XSU TABLE or CONTENTS. 

CHAPTER VII. 
Mineral Constituents, or Ashes, of Plants 120 

CHAPTER VIII. 
Animal Chemistry <... 125 

CHAPTER IX. 
Sources from which Plants derive their Nourishment 189 

CHAPTER X. 

General Principles of Vegetable Physiology 144 

CHAPTER XI. 
Structure and Functions of the Organs of Plants 149 

CHAPTER XII. 
The Soil — its Geological Origin, &c 168 

CHAPTER XIIL 
Mechanical Management of the Soil 195 

CHAPTER XIV. 
Chemical Treatment of the Soil 210 

CHAPTER XV. 
History and Properties of Special Manures 227 

CHAPTER XVI. 
Application of Fertilizers — Planting and Culture of Crops 255 



TABLE OF CONTENTS. XXIU 

CHAPTER XVII. 
Culture of Indian Corn 268 

CHAPTER XVIII. 
Culture of Wheat and Oats 280 

CHAPTER XIX. 
Planting and Culture of Potatoes 287 

CHAPTER XX. 
Hay Crops and Pasture 293 

CHAPTER XXI. 
Beans and Peas — especially the "Southern Pea" 301 

CHAPTER XXII, 
Culture and Management of Tobacco 311 

CHAPTER XXIII. 
The Cotton Crop 330 

CHAPTER XXIV. 
Rotation of Ci'ops 342 

CHAPTER XXV. 
Value of Crops as Food 354 

CHAPTER XXVI. 
Animal Physiology 363 



XXIV TABLE OF CONTENTS. 

CHAPTER XXVII. 
Selection and Preparation of Food 405 

CHAPTER XXVIII. 
Selection and Care of Stock 418 



SCIENTIFIC AND PRACTICAL 
AGRICULTURE. 



CHAPTER I. 

INTRODUCTION. 

§ 1. Agriculture may be viewed in the two-fold light 
of a science and an art. As a science, it embraces some of 
the leading principles of Chemistry, Geology, and of Ve- 
getable and Animal Physiology. As an art, it consists in 
the skilful application of science to the cultivation of the 
soil, so as to make it yield the largest crops at the least 
possible cost. It also embraces the proper management and 
feeding of such animals as belong to the farm. 

We shall first define the several branches of science in- 
volved in our general subject; then discuss each of them 
briefly, giving only such principles and illustrations as may 
be applicable to domestic and agricultural pursuits. 

2. Chemistry treats of the composition and properties of 
all substances on the surface of the earth. Soils, manures, 
and all vegetable and animal substances, have their true 
composition determined by chemical research. Chemistry 
also explains the various changes which take place in the 
growth and decay of plants and animals. 

3 (25) 



2G INTRODUCTION. 

3. Geology examines into the structure of the earth, the 
nature of rocks, and the origin of soils. 

4. Pliysiology makes us acquainted with the various 
organs of plants and animals, and the part they act in pro- 
moting growth, nutrition, etc. 

5. Chemical Experiment. — Take a few grains of iron 
filings, and mix them with an equal weight of finely- 
powdered sulphur. If you now examine the mixture, you 
find the particles of iron and sulphur still distinct from 
each other — the mass is a simple mixture. Place the mix- 
ture upon a piece of porcelain cup, and heat it over hot 
coals or a spirit-lamp, until the sulphur takes fire and all 
the surplus sulphur is burnt out. The resulting mass will 
be found to difiier entirely from both iron and sulphur. 
The two substances have united in one ; they have become 
a compound substance. While they were still in separate 
particles they were simple or elementary substances. The 
force which caused them to unite when heated, is called 
chemical affinity. 

6. Definition. — A simple or elementary substance is one 
which cannot be separated into two or more parts, which 
dift'er from each other in their properties. 

Illustration. — Sulphur maybe ground to a fine powder, 
yet all the particles will possess the same properties. Sul- 
phur, then, is an elementary substance. Water may be 
separated by the galvanic battery into two gases, having the 
form and appearance of the air; but they difier very widely 
from each other in many of their properties. Water is not 
an elementary substance. But neither of the gases of which 
water is composed, can be again divided into parts having 
different properties. These gases are elementary substances, 
and are called oxygen and hydrogen. 

7. Definition. — A compound suhstance is one formed by 
the combination of two or more elementary substances. 



INTRODUCTION. 27 

lUusfration. — When iron and sulphur were heated together 
(§ 5), they united into one mass similar in all its parts. This 
combination of iron and sulphur is a chemical comjwxind. 
We call it sulphurct of iron. Oxygen and hydrogen, when 
combined, form water, which is a compound. 

8. Definition. — Chemical affinity is the force which causes 
elementary substances to combine and form compounds, 
and compounds to combine with each other and form new 
compounds. 

Illustrations. — The force which causes iron and sulj)hur 
to combine is chemical afRnity. A piece of limestone or 
marble is composed of lime and a gas called carbonic acid. 
These are kept together by affinity. If the stone is heated 
red hot for some time, the gas is expelled, and the lime alone 
is left. The power of affinity between them has been over- 
come by heat, and the stone is said to be decomposed. 

Keeping before our minds the definitions of elementary 
and compound substances, and of affinity, let us now define 
Chemistry. 

9. Definition. — Chemistry is the branch of science which 
treats : 1. Of the history and properties of elementary sub- 
stances ; 2. Of the formation and properties of compounds ; 
3. Of the latvs icliich regulate the action of affinity. 

There are certain agencies which have a great influence 
over chemical affinity. These are Heat, Light, Electricity, 
and Vitality. We must here study some of their properties 
and eficcts, before we enter upon the study of chemistry in 
its more restricted sense. 



QUESTIONS ON CHAPTER I. 

\ 1. How ma/ Agriculture be viewed? As a science, what does 
it embrace ? What as an art ? 

2. Of what does Chemistry treat? How is the true compositioa 
of all substances detei-mined ? 



28 INTRODUCTION. 

3, 4. What is Geology? Physiology? 

5. What chemical experiment is here given? What is the product? 

6. AVhat is a simple or elementary substance? Illustrate it. Is 
water simple ? Of what composed ? 

7. What is a compound substance ? Illustrate. 

8. What is chemical affinity ? Illustrate. 

9. Define Chemistry. What agencies influence chemical affinity ? 



To Teachers. — The questions inserted at the end of each chapter are merely 
designed to be Buggestiye to young teachers. Every teacher should, of course, 
frame hi.s own questions, to suit circumstances. For my own part, I never use the 
questions given in any text-book; nor do I regard those given here as of much 
importance. Still, the young teacher, in the preparation of the lesson in advance 
of bis class, may get some good suggestions by reading the questions over, after he 
has studied the text. 



HEAT. 29 



CHAPTER II. 

HEAT — LIGHT — AND ELECTRICITY. 

10. The term caloric is often applied to tlie agency "whicli 
causes the sensation called heat ; but we shall use the word 
HEAT to denote both the cause and the sensation. 

Heat is a most important agent in pi'omoting, modifying, 
or destroying the force of affinity. Many substances which 
do not combine at ordinary temperatures, combine rapidly 
when heated. We had an illustration of this in the experi- 
ment witli iron and sulphur. In the burning of limestone 
(§ 7), affinity was destroyed, or at least overpowered, by 
heat. The action of affinity also produces heat, as in the 
burning of a lamp or fire. 

11. Sources of lie at. — The sun is the greatest source of 
heat. Combustion, electricity, and friction are sources of 
heat on the earth. Heat is thrown out from its sources in 
straight lines. It is then said to be radiated. 

12. When radiated heat falls upon the surface of a body, 
and, entering, pervades the particles of that body, it is said 
to be absorbed. If the heat is thrown off by the surface 
upon which it falls, it is said to be reflected. 

Experiment. — Take two tin vessels of the same form 
and size. Let one of them be bright, and paint the other 
with lampblack. Fill both nearly full of cold water, and set 
them in front of the fire. The water in the vessel with the 
black, rough surface will be heated most rapidly. The 
polished, bright surface reflects the heat, while the black, 
rough one absorbs it. Again, fill the two vessels with hot 
3* 



30 II EAT. 

water, and set them aside to cool. A thermometer in each 
will show that the black vessel cools off most rapidly. Black, 
rough surfaces radiate more rapidly than bright ones. A 
stove should be dark and rough — we wish it to radiate as 
much as possible. A coffee or tea-pot should be bright and 
smooth, that it may retain the heat. Dark soils are warmed 
more rapidly in the spring by the sun, than are those of 
light color. 

13. Conduction of Heat. — Heat passes from particle to 
particle very rapidly in some bodies, while it passes very 
slowly in others. Hold a piece of iron and a piece of glass 
in the flame of a candle at the same time. The heat soon 
reaches the fingers through the iron, but the glass may be 
held in the flame for many hours without conveying the 
heat to the hand. Bodies through which heat passes freely 
are conductors. Those through which it passes very slowly 
are non-conductors. Metals are good conductors. Glass, 
charcoal, dry wood, and most liquids, are non-conductors. 
We clothe ourselves with non-conductors in winter, to con- 
fine the heat of the body. We surround ice-houses and 
refrigerators with non-conductors, to keep out the heat of 
the sun and earth. 

Experiment. — To show that water is not a conductor, 
PiQ, 1^ drop a little lump of ice into the 

bottom of a test-tube (Fig. 1), and 
fasten it down with a coil of wire. 
The water may then be boiled at 
the top of the tube, Avhile the ice 
remains unmelted in the bottom. 

EFFECTS OF HEAT. 

14. Expansion. — Bodies of all forms, solids, liquids, and 
gases, are expanded by heat. Exps. — 1. Let the metallic 
bar (a) be made exactly to fit the frame (h) (Fig. 2), at 




HEAT. 



31 



Pig. 2. 



'tn^-lWlflllj^ 



-3 



Fig. 3. 



ordinary temperatures ; tlien, when heated, the bar will be 
too long for the frame ; and when cooled with ice, it will be 
shorter than the frame. 2. Fill the 
glass bulb and tube (Fig. 3) with 
water to the point a, and mark that 
point; then hold the bulb over a 
lamp, or dip it into hot water. The 
water in the tube will soon rise above 
a, by the expansion of the portion in 
the bulb. Alcohol will expand still 
more than water with the same in- 
crease of temperature. 3. Pour the ^ 
water out of the bulb and tube, and 

invert the tube, placing the mouth of it under water, in the 
tumbler (6). The tube and bulb will then be full of air 
alone, but if the bulb is clasped in 
the hand until it becomes warm, the 
heat will be communicated to the air 
within, and expand it to such ah ex- 
tent, that a portion will be expelled, 
and pass out in bubbles through the 
water. A lamp flame applied to the 
bulb will expel the air still more 
rapidly. As the bulb cools again, 
the air within contracts, and, oc- 
cupying a smaller space, allows the 
water to be forced upward towards 
the point c, by the pressure of the surrounding atmosphere. 
15. Practical Applications. — When a blacksmith wishes 
to fit the tire upon a wagon-wheel, he guages it so that, 
when cold, it is a little smaller than the wooden rim of the 
wheel. He then expands it by heat, until it is larger than 
the wheel. It is then easily put on, and, to cool it, the 
wheel is turned on an axis, with the rim dipping into a 




33 



HEAT. 



Boiling. 



trough full of water, the workman, meantime, adjusting it 
properly with his hammer. As it contracts, the wheel is 
bound together with great force. The wheels of wagons 
often become loose in hot weather, partly by the drying of 
the wood of which they are made, but partly, too, by the 
expansion of the tii-e under the sun's heat. 

16. We have a beautiful and useful application of the 
expansion of liquids, in the construction of the common 
thermometer (Fig- 4). 
•pjj,_ 4_ " Ordinary thermometers consist simply 

^-~. of a glass tube of an exceedingly small 

bore, with a bulb blown at one extremity, 
and filled with mercury to about one-third 
the height of the stem. The air being 
expelled, the tube is hermetically sealed, 
and the freezing-point ascertained by hold- 
ing it a short time in water containing ice, 
and the boiling point by holding it in the 
same manner in boiling water. It is neces- 
sary that these two points should be accu- 
rately determined, in order that the indi- 
cations of diiferent instruments may be 
compared with each other. 

'' Having determiiied these points, the 
intervening space is to be divided into 
equal parts, called degrees ; and in fixing 
upon the proper number, regard to conve- 
nience alone would seem to be our guide. 
Unfortunately, there have been different opinions with regard 
to this point, and no less than three different scales are in 
use. In Fahrenheit's thermometer, which is chiefly used in 
this country and in England, the space between the freezing 
and boiling points of water is divided into 180 parts, and 
the zero is placed 32 degrees below the freezing point, so 



HEAT. 33 

that the boiling point is at 212. In the Centigrade thermo- 
meter, which is generally used in France, the space is divided 
into 100 parts, zero being at the freezing point, and of course 
the boiling point is at 100. In Reaumur's thermometer the 
beginning of the scale, or zero, is at the freezing point ; but 
the boiling point is at 80. This thermometer is used in 
Germany and Russia." — Johnston's Turner. 

17. Water follows the ordinary laws of expansion and 
contraction, only within certain limits. When cooled below 
the ordinary temperature, it contracts, until the temperature 
is brought down nearly to 89° F. It then begins to expand, 
and continues to do so until, at the moment of freezing, 
there is a sudden expansion, so great as to make ice consi- 
derably lighter than water, and thus cause it to float upon 
the surface. This property of water points us in a striking 
manner to the wisdom and benevolence of our Creator; for, 
if water had been so constituted as to follow the law of con- 
traction, as exhibited in bodies generally, it would sink as it 
freezes, leaving the surface always exposed; and thus, in cold 
climates, one portion after another would freeze and sink, till 
all the streams and lakes would become solid masses of ice. 
But as the ice floats upon the surface, it protects the body 
of water beneath, and prevents its too rapid fz-eezing. 

The expansion of frozen water in the pores of the soil, 
enlarges those pores ; thus rendering the soil easily culti- 
vated, and leaving it, in the spring, in condition to be readily 
penetrated by the roots of plants. 

18. The expansion of air by heat serves many valuable 
purposes. Heated air, by becoming lighter, is forced upward 
by the mass of cooler air which surrounds it. Thus, the 
heated air in a fire-place or stove is made to pass rapidly up 
the chimney or pipe, and carries the smoke with it. So when 
some portions of the atmosphere become more highly heated 
than others, they rise, while the surrounding portions flow in 



31 HEAT. 

to take their place. Thus, currents of wind are produced. 
In this way, the Creator has provided that our atmosphere 
shall be kept in a state of perpetual circulation, by the 
varying heat of the sun. 

FORMS OF BODIES. 

19. Solids, Liquids, Gases. — All bodies on the earth have 
one of three conditions — they are solid, liquid, or gaseous. 
These conditions are determined chiefly by temperature. 
For example, water is solid below 32° ; liquid, between 32° 
and 212°; gaseous (steam) above 212°. Mercury is solid at 
40° below zero; while between that temperature and 662° 
it is liquid. Heated to a still higher temperature, it assumes 
Yjq 5 the gaseous form. Boiling is the agitation produced 
by the rapid formation of steam or other vapor at 
the bottom of a portion of liquid, and the rising 
of the bubbles of the steam thus produced. The 
boiling of water may be beautifully exhibited by 
filling a glass flask (Fig. 5) half full, and placing 
a spirit-lamp under it until it boils. 

20. Insensible or Latent Heat. — When the heat of a body 
is so modified as not to be felt by the hand, or so as not to 
afi'ect the thermometer, it is said to be rendered insensihle or 
latent. Heat becomes insensible when a solid is changed to 
a liquid, or when a liquid is changed to vapor. 

When ice is made to melt rapidly by mixing it with a 
substance like common salt, for which it has an affinity, the 
heat already in it becomes insensible, and the temperature 
falls rapidly. 

Experiment. — Reduce two pounds of ice to fine powder, 
and mix it thoroughly with one pound of salt. A thermo- 
meter inserted in the mixture will soon fall below zero. A 
little water in the bottom of a test-tube, immersed into the 
mixture, will be frozen in a few minutes. 



HEAT. 



Fig. 6. 



Tq freezing ice-cream, we have an illustration of a similar 
kind. But, in this case, a smaller quantity of salt should be 
used, so that the freezing may not be too rapid. The cream 
has a finer grain if frozen more gradually, and frequently 
agitated as it freezes. 

21. When water is heated up to 212°, it begins to boil. 
A thermometer immersed into the water will cease to rise as 
soon as the boiling commences. Unless the water is confined 
by external pressure, it cannot be heated above 212°. The 
steam, as it rises from the water, has the same temperature 
as the boiling water. But after water has been heated to the 
boiling point, it still requires a great amount of heat to con- 
vert it into steam. This added heat becomes insensible in 
the steam. 

22. The boiling point of a liquid, such as water, is greatly 
modified by outward pressure. The atmosphere 
at the surface of the sea exerts a pressure of 
about 15 jjounds on every square inch of surface. 
On the tops of high mountains, the pressure is 
much less, because a large portion of the atmo- 
sphere is beneath us. Here water will boil below 
212°. If the pressure of the air can be dimi- 
nished in any other way, a similar result follows. 

Experiment. — Fill a glass flask half full of 
water (Fig. 6), and boil it a few minutes, till the 
air is all expelled by the steam. While still 
boiling, cork it tightly, and invert it into a glass 
tumbler or cup, with a little water in the bottom. 
Apply a cloth dipped in cold water to the top of 
the flask as now inverted, and the water will boil 
violently. This will take place even after the 
flask becomes cool enough to be held comfortably in the 
hand. If hot water is applied to the outside of the flask, 
instead of cold, the boiling will cease. To understand this 




36 



HEAT. 



beautiful and interesting experiment, we must remember that 
the air has all been expelled, and nothing but the vapor of 
water remains above the surface of the water in the flask. 
When cold water is applied, this vapor is rapidly condensed, 
and its pressure on the water diminished. Under this dimi- 
nished pressure, the water boils at a low temperature. Hot 
water, however, instead of condensing the vapor, tends to 
expand it; and thus the pressure is increased, and the 
boiling checked. 

23. Distillation. — Two liquids, which boil at different 
temperatures, may be separated by distillation ; or a volatile 
liquid may be separated from involatile substances held in 
solution by it. 

Experiments. — 1. Put a mixture of equal parts of alco- 
hol, and water in the retort, a (Fig. 7). Insert the neck of 

Fig. 7. 




the retort into the receiver, h, kept cool by being placed in a 
basin of cold water. Apply a lamp to the retort, and regu- 
late the heat so that the boiling will go on slowly. As the 
liquid disappears from the retort, a portion of it will be found 
condensed again in the receiver. When about the half of it 
has thus passed over to the receiver, examine the two por- 



HEAT. 37 

tions; and it ■will be found that what is left in the retort is 
much weaker than the original mixture, while that portion 
in the receiver is much stronger. The alcohol, being more 
volatile than water, has passed over more rapidly. 2. Empty 
the retort and receiver, and use clean spring-water instead 
of the mixture. The mineral matter, some of which is 
always found even in the purest springs, will remain in the 
retort; while pure water will be collected in the receiver. 
Water should be thus distilled before it is used in preparing 
solutions of chemical substances. 

24. Atmospheric Vapor. — Water is continually evapo- 
rated from the surface of the earth, from rivers, seas, and 
oceans, and, ascending, mingles with the air in vast quanti- 
ties. It is found in the atmosphere in two conditions. (1) 
In a visible form, as clouds and fogs. (2) In the form of 
true vapor, which is entirely invisible. If the air were 
removed, that is, if the space above the surface of the 
earth were a vacuum (wnth reference to air), evaporation 
would go on much more rapidly than it now does, until the 
whole world would be surrounded by an atmosphere of 
vapor. The air checks evaporation. 

The quantity of vapor required to fill a given space, at a 
maximum density, varies with the temperature (below 212" 
F.), increasing as the temperature rises, and diminishing as 
the temperature falls. When the space is entirely filled, the 
vapor is said to have its " maximum density," for the tem- 
perature it then has. The vapor of water required to fill a 
cubic foot of space, at 32° F., weighs about 2 J grains; 
while that required to fill the same space, at 212°, weighs 
258j grains. If the vapor were heated only to 100°, then 
19 4 grains would fill the cubic foot of space. 

25. Although the presence of the air causes evaporation 
to go on more slowly, yet the quantity of vapor which will 
ultimately be required to fill a given space, at any given 

4 



88 11 E A T. 

temperature, will always be the same, whether the air is 
present or not. And the vapor will not cease to rise till it 
has reached its maximum density. Whenever this takes 
place, the air is generally said to be " saturated with mois- 
ture." The temperature of the vapor mingled with the air 
varies with the temperature of the air. When the vapor 
has its greatest density at any temperature, and the air is 
cooled below that temperature, the vapor is also cooled. Less 
of it will then saturate the air (or fill the sjiace), and the 
remainder must be condensed into the form of water. 

When the air is cooled down until the vapor which it 
contains begins to be deposited as little particles of moisture, 
that temperature is called the " dew-point." 

26. If the vapor in air has nearly its greatest density, the 
air is said to be damj) ; but if there is not vapor enough 
present to give it near its greatest density, the air is said to 
be dry. If damp air has its temperature reduced but a few 
degrees, a part of its moisture is condensed ; but if its tem- 
perature is elevated a few degrees, it becomes apparently 
dry ; that is, its vapor, with the increase of temperature, is 
no longer capable of filling the space it occupies. On the 
other hand, dry air may become damp by being cooled ; for 
the reduction of temperature may be sufficient to bring the 
vapor to its state of greatest density for that temperature. 
It is then readily deposited as moisture. 

When the temperature of air is reduced below the dew- 
point, a portion of the vapor present becomes condensed, and 
assumes a visible form, either like deic, on the surfaces of 
solid bodies, or like jh/s/, floating in the air. 

27. Dew and Frost. — Experiments. 1. Fill a bright 
cup of silver or tin half full of water, and place a thermo- 
meter in it. Wipe the outer surface of the cup perfectly 
dry; then drop small lumps of ice into the water at short 
intervals. On a warm summer day, the moisture from the 



H E A T. 39 

air will soon begin to dim the bright surface of the cup. 
The temperature indicated by the thermometer at that mo- 
ment, is the temperature at which the vapor of the air 
begins to be condensed: it is the dew-point. — 2. Put a 
mixture of ice and salt into the cup, instead of ice-water, 
and the moisture will be frozen as it collects upon the sur- 
face. It is then frost — frozen dew. 

After the sun, the great source of heat, has gone down, 
solid bodies on the earth radiate their heat rapidly into the 
atmosphere, while the atmosphere itself radiates but slowly. 
As these bodies radiate heat, their temperature gradually 
falls; and they cool down the particles of air which come 
in contact with them, and also the particles of vapor mingled 
with the air. Whenever the temperature is thus brought 
below the dew-point, dew begins to be deposited. When 
the receiving surfaces are below 32°, the dew is frozen, and 
becomes frost. 

28. If the air is agitated by winds, dew and frost are not 
so readily deposited ; because no portion of the air is then 
allowed to remain long enough in contact with the cold sur- 
faces of bodies on the ground, to be brought down to the 
required temperature. In low valleys we very frequently find 
vegetation covered with dew or killed by frost, while the same 
efiects are not produced on the surrounding hills. This is 
owing to the fact, that the confined portions of air along the 
valleys remain tranquil, while those on the hills are disturbed 
by currents of wind. 

Clouds reflect the heat radiated from the earth's surface, 
and thus prevent the temperature from being reduced to the 
dew-point. Hence, there is no dew on cloudy nights. 

Surfaces which radiate most freely are cooled most rapidly 
at night, and consequently collect dew in greatest abundance. 
This is the case with green vegetable substances. Plants 
which especially need the dew, have thus been organized by 



40 HEAT. 

an all-wise Creator, that they might collect it readily from 
the air. In some countries, the dews are almost the only 
source of moisture for plants for many successive weeks. 

29. Rain. — When two equal portions of air at widely differ- 
ent temperatures are mingled, the resulting temperature will 
be a mean between the two. But if both portions were nearly 
saturated with moisture before they were mingled, this mois- 
ture can now no longer remain in the form of vapor; because 
the quantity of vapor required to fill the space occupied by 
the two bodies of air at their mean temperature, is less than 
was required when they had widely different temperatures. 
A portion of the vapor, then, must be changed to mist or dotid. 

Illustration. — 5000 cu. inches of air at 32° can contain 
only about 10 grains of vapor. 

5000 cu. inches of air at 59° can contain only about 20 
grains of vapor. 

5000 cu. inches of air at 86° can contain as much as 40 
grains of vapor. 

Now, suppose the first portion of 5000 cu. inches, at 32°, 
to be mingled with the third, at 86° : their mean tempera- 
ture will be that of the second portion (59°); but the re- 
sulting 10000 cu. inches, at this temperature, can contain 
only 40 grains, while they unitedly had 50 grains before 
they were brought together. The surplus 10 grains of vapor 
must now appear in a condensed form. When currents in 
the atmosphere meet and mingle in this way on a large scale, 
immense quantities of moisture are condensed in the form 
of minute hollow globules, which, uniting, form rain-drops, 
and fall to the earth. If, from great elevation, or any other 
cause, the drops become frozen before they reach the earth, 
they come down as hail or sleet. When the moisture is 
condensed at a temperature below 32°, it forms minute 
crystals, instead of globules; and these, Ainiting in clusters, 
form Jlakcs of snow. 



HEAT — L-I G II T. 41 

30. Fogs are clouds formed near the earth's surface. This 
happens around islands and along the sea-shore, when the 
cool air from elevated land flows down and mingles with the 
warm, moist air over the surface of the water. The same 
phenomenon is witnessed in valleys, and especially along- 
large rivers, in spring and autumn, when the days are warm 
and the nights cool : the cool, dense air from the surround- 
ing hills flows down and mingles with the warmer air along 
the water. Whenever such a mingled mass of air has a 
temperature too low for all its moisture to retain the form 
of vapor, a portion of fog will make its appearance. 

Fortunate is it for our comfort, that the air plays so con- 
spicuous a part in regulating the evaporation of moisture. 
We can see the hand of a kind Providence in so constitu- 
ting the air, that it presents a perpetual impediment to eva- 
poration. If it had been so constituted that evaporation 
and condensation could go on as freely in it, as they do In 
vacuo, the atmosphere would be ever reeking with moisture : 
no sooner would a slight elevation of temperature take place, 
than a sudden rise of vapor from the earth would follow, and 
the vapor of the air be brought to the condition of maxi- 
mum density. Then, every portion of the atmosphere being 
in this condition, the least diminution of temperature would 
produce a cloud or a mist; and every object surrounded by 
the air would be drenched by a copious deposit of dew, 
whenever by any means its temperature happened to fall 
below that of the atmosphere. Drought and drenching 
would then be the alternate efiects of elevations and de- 
pressions of temperature. 

LIGHT. 

31. We shall not stop to discuss the nature of light, nor 
any of its effects, except such as relate to our immediate 
subject. 

4* 



42 Lie. II T. 

32. The great natural source of light is the sun. Artifi- 
cial light is generally the result of heat produced by chemical 
action ; by combustion. Whatever may be the source of 
light, it passes off from luminous bodies in straight lines; 
and is either absorbed by the bodies on which it falls j or is 
thrown back from their surfaces {i'( fleeted) ; or passes through 
them (transmitted^. Reflected light enables us to see the 
objects around us, by passing from them to the eye. The 
colors of objects are determined by the manner in which 
they reflect light. 

33. Light has a remarkable effect upon the heat which 
accompanies it. This is seen in some of the peculiarities 
of the heat produced by the sun. The light seems to have 
the effect of making it pass freely through transparent sub- 
stances, such as air and glass, without affecting their tempe- 
rature to any considerable extent. If this were not the case, 
but little of the sun's heat would reach the earth. The heat 
of the sun accompanied by light, has the property of being 
absorbed more freely by dark surfaces, than heat without 
light. 

34. The effects of light on chemical afiinity are remark- 
able. Some substances are decomposed by it, while others 
are caused to combine. 

Experiment. — Moisten a piece of white paper or linen 
with some solution of lunar caustic (nitrate of silver), and 
lay it for a few minutes in the sunlight. It will become 
dark — almost black. Here the light decomposes the nitrate 
of silver. 

Illustrations. — The effect of light upon chemical action is 
beautifully illustrated in the process of taking Daguerreo- 
types, ambrotypes, etc. 

Light is necessary to the healthful growth of plants and 
animals. Every one is familiar with the difference in the 
appearance and vigor of the same kind of plant, when 



ELECTRICITY. 43 

growing in a shaded place, and in the full light of the sun. 
Very few plants will come to full maturity without a full 
supply of light. Animals, too, generally require light. The 
lower animals, as well as men, never attain to much vigor if 
they are shut up in the dark during the period of their 
growth. 

ELECTRICITY. 

35. That form of electrical excitement produced by the 
galvanic battery, is one of the most powerful chemical 
agencies within our reach, and enables us to perform some 
of the most interesting and striking experiments. But our 
present purpose demands only a few of the leading facts 
and principles on this subject; such as are necessary to 
a clear and full understanding of the laws of chemical 
affinity. 

36. *' When two solid conducting bodies are plunged into 
a liquid which acts upon them unequally, the electric equili- 
brium is also disturbed — the one acquiring what is called 
the positive condition, and the other the negative. Thus, 
pieces of zinc and platinum (or copper), put into dilute sul- 
phuric acid (oil of vitriol, with 5 or 6 parts of water), con- 
stitute an arrangement capable of generating electrical force : 
the zinc, being the metal attacked, becomes negative (above 
the liquid) ; and the platinum (or copper) re- p « 8 
maining unaltered, assumes the positive con- ^ ^^ 
dition; and on making the metallic communi- 
cation in any way (as at a, Fig. 8) between 
the two plates, a discharge ensues, as when 
the two surfaces of a coated and charged jar 
are put into connection. 

" No sooner, however, has this occurred, 
than the disturbance is repeated; and, as these successive 
charges and discharges take place through the fluid and 
metals with inconceivable rapidity, the result is an appa- 




44 



ELECTRICITY. 



rently continuous action, to wliicli the term electrical current 
is given." — Fownes. 

37. With a single pair of plates, as above described, the 
degree of excitement is very feeble; but if we arrange 
several pairs as in Fig. 9, having the zinc and copper in 

Fig. 9. 




contiguous cups connected by wires soldered to each other, 
and placing them so that the difl'crcnt metals shall succeed 
each other in the same order; then connect the first and last 
plate by wires (a, h), we have a compound circuit. This 
gives us the simplest form of the galvanic battery, 
ends of a and h are called the poles of the battery. 
one marked, -{-, is the positive; and the one marked, 
the negative. 

38. Another very simple form of the battery is repre- 
sented in Fig. 10. It consists of a wooden trough with per 

Fig. 10. 



The 
The 
-, is 




pendicular grooves in the sides, and corresponding grooves 
across the bottom. Into these are fitted pairs of zinc and 



ELECTRICITY, 



45 



copper plates, soldered back to back, and having all the 
copper plates facing the same way. They are then to be 
carefully cemented into the grooves. The trough is thus 
divided into cells for holding the mixture of acid and water 
with which the battery is charged. At the extremities of 
the last cells, plates are to be inserted for the connecting 
wires : one of zinc, so placed as to be opposite to and facing 
the last copper; the other of copper, facing in like manner 
the zinc at the opposite end of the trough. 

39. There are various other forms of the battery in use, 
among the best of which is Grove's. This is the one most 
commonly used on telegraph lines. We have not room for a 
description of it here. It is described in most of the larger 
works on Chemistry. 

40. Whatever may be the form of the battery, if the poles 
are tipped with little strips of platinum foil, and immersed 
into water, to which a little sulphuric acid has been added, 
bubbles of gas will rise rapidly around both poles. The water 
is decomposed. The oxygen and hydrogen of which it is 

Fig. 11. 




composed are separated ; the oxygen collecting around the 
positive pole, and the hydrogen around the negative. These 



46 ELECTRICITY. 

gases may be collected by filling test-tubes with water, and 
inverting them over the poles of the battery, by some such 
arrangement as that seen in Fig. 11. The tube over the 
negative pole, into which the hydrogen passes, will be filled 
twice as rapidly as the other; showing that the hydrogen of 
water occupies twice the volume of the oxygen. But if we 
could weigh the two gases, we would find the oxygen eight 
times as lieavi/ as the hydrogen. 

41. Experiment. — Mix a few grains of starch with a 
spoonful of cold water; then add the mixture slowly to half- 
a-pint of boiling water, stirring as you pour it in. You will 
thus get a dilute solution of starch. When this has become 
cold, pour into it a little of the solution of iodide of potas- 
sium. Then put the mixture into a tumbler, and bend the 
poles of the battery over the opposite sides of the tumbler, 
so that the strips of platinum will dip a little way into the 
solution. If the battery is now put into action, the solution 
soon becomes of a deep blue color around the positive pole, 
while there is no change of color around the negative. The 
battery decomposes the iodide of potassium, which is com- 
posed of iodine and potassium combined. The iodine is 
collected around the positive pole, free from the potassium, 
which has gone to the negative pole. But so soon as the 
iodine is set free, it attacks the starch in the solution, and, 
uniting with it, forms a beautiful blue compound, called 
iodide of starch. The starch in the solution is not aifected 
by the battery: it is used in this experiment to show the 
presence of the free iodine around the positive pole. 

IMany other substances may be decomposed with the bat- 
tery; but the above will serve to illustrate, sufficiently for 
lOur present purpose, the action of this wonderful piece of 
apparatus. 

The influence of Vitality will be shown in connection with 
organic chemistry. 



QUESTIONS. 47 



QUESTIONS ON CHAPTER II. 

§ 10. How is the term "caloric" applied? In what sense is 
"heat" here used? Why is heat an important agency to the 
chemist? 

11. What is the greatest source of heat ? AVhat are other sources? 

12. When is heat said to be absorbed? When i-eflectcd ? Illus- 
trate. What kind of surface should a stove have? Why? Coffee- 
pot? Why? How does dark color affect soil ? 

13. What bodies are conductors? Non-conductors? Is water a 
good conductor? How illustrated by experiment? 

14. What is the influence of heat on the dimensions of a body? 
What experiments illustrate expansion of solids ? Of liquids ? Of 
gases ? 

15. IG. How is a tire fitted to a wagon- wheel? Explain the struc- 
ture of the common Thermometer. What principle does its action 
illustrate ? 

17, 18. To what degree of temperature does water contract when 
cooled? AVhat takes place at the moment of freezing? What would 
be the result if contraction should continue, with continued reduc- 
tion of temperature? Why does ice float? IIow does freezing 
affect the soil? What are the effects of expansion and contraction 
in the air? 

19. In what conditions do all bodies exist? What determines 
these differences in form ? How illustrated ? 

20. What is insensible heat ? Why does the temperature fall 
rapidly in a mixture of salt and ice ? Explain the preparation of 
ice-cream. 

21. At what temperature does water boil? If a thermometer is 
immersed in it, will it rise above 212°? What becomes of the heat 
continually added ? 

22. How does change of pressure influence the boiling point? 
How illustrated? AVhy does cold water applied to the flask increase 
the boiling, while hot water diminishes it? 

23. What kind of substances may be separated by distillation? 
How are alcohol and water separated ? How is water purified ? Is 
not spring-water pure? Why not? 

24. From what sources does the air receive moisture ? In what 
conditions does moisture exist in the air? What determines the 



48 QUESTIONS. 

quantity of vapor required to fill a given space below 212° ? When 
has vapor its greatest density ? Illustrate. 

25. Does the presence of air diminish the quantity of vapor re- 
quired to fill a given space? IIow does the temperature of the air 
influence the temperature of the vapor present? What is meant by 
the " dew-point"' ? 

26. When is air damp ? AVhen dry ? What if the temperature 
of damp air be reduced? V/hat if it be elevated? How maj' dry 
air be made apparently damp ? When does the vapor become visible? 

27. Explain the deposition of moisture on the surface of a cool 
cup. When does it become frost ? How arc dew and frost formed 
at night ? 

28. Influence of winds on the formation of dew? Why is vege- 
tation frequently killed by frost in valleys, while it escapes on the 
surrounding hills? lIow do clouds prevent dew and frost? What 
surfaces receive most dew? Who made this provision? Why? 

29. When do mingled portions of air form clouds ? How illus- 
trated? How ai-e rain-drops formed? Hail? Snow? 

30. What are fogs? Where most frequently seen? Why? If 
the air did not regulate evaporation and condensation, what would 
be the consequence ? 

31. 32. Great natural source of IJght ? Sources of artificial light? 
In what ways is light disposed of when it falls upon the surface of 
bodies? What determines color? 

33. Influence of light on transmission of heat? How is the air 
heated? 

34. What is said of influence of light on affinity? How illus- 
trated? Influence on vegetation? 

35. 36. What is said of Electricity produced by the galvanic bat- 
tery ? What if two solid conductors are acted upon unequally by an 
acid liquid? Explain Fig. 8. What is called the "electric current"? 

37, 38, 39. Effect of increasing the number of plates ? Explain 
Fig. 9. How is a battery constructed ? 

40, 41. How is water decomposed by the battery ? What experi- 
ments are here given? 



SYMBOLS — E Q U I VA L E N T S . 49 

CHAPTER III. 

SYMBOLS — EQUIVALENTS — NOMENCLATURE. 

42. There are sixty-five elementary substances known to 
chemists (see § 5). These unite and form all the various 
compounds of v?hich we have any knowledge. Many of 
them, however, are rare and unimportant. We shall take 
time to describe only twenty-eight of the most important. 
These will be found in a table on the next page. 

SYMBOLS. 

43. It is not always convenient to write the names of sub- 
stances in full; hence we employ what are called syvihols. 
These consist of the first letter, or some two letters, of the 
names ; thus, C is the symbol for carbon ; H for hydrogen ; 
Al for aluminum; Mn for manganese. When the substance 
has a Latin name, we use the first letter or letters of this 
as its symbol ; thus, K stands for potassium (from lialium, 
its Latin name). So Sb (from stlhiuiii) is the symbol for 
antimony ; and Fe (from ferrmn) for iron. 

EQUIVALENTS. 

44. When elementary substances combine to form com- 
pounds (§ 5 and 6), they enter into the compounds in defi- 
nile proportions by weight. Hydrogen and oxygen are com- 
bined in water, in the proportion of 1 to 8 (§ 40). That is, 
the oxygen in water (in all pure water) weighs eight times 
as much as the hydrogen. When hydrogen and sulphur 
combine to form the disagreeable gas which rises from sul- 
phur springs, the proportion is 1 of hydrogen to 16 of sul- 
phur. And as hydrogen enters into combination in a less 

5 



50 



EQUIVA LENTS. 



relative weiglit than any other elementary substance, we take 
its combining weight as 1 ; then that of oxygen will be 8 ; 
and that of sulphur 16. These numbers are supposed to 
represent the relative 7cei<jh(s of tlie atoms, or smallest parti- 
cles, of the substances to which they belong; hence they are 
called atomic iceights, or comhining equivalents. 

Iron may take the place of hydrogen in some compounds, 
and cause the hydrogen to escape; but, for every singh 
grain of hydrogen displaced, twenty -eiglit grains of iron must 
enter to fill its place. If single atoms of iron have displaced 
single atoms of hydrogen, the atoms of iron must weigh 
twenty-eight times as much as the atoms of hydrogen. The 
28 parts of iron are said to be equivalent to 1 part of hy- 
drogen. The number 28, then, represents the combining 
equivalent of iron ; or, which is the same thing, its atomic 
iceiglit. This last is the term by which we shall designate 
these numbers. 

45. The symbols and atomic weights of some of the most 
important substances are given in the following 

TABLE I. 



NAMES. 

Aluminum... 

Antimony (Stibium). 

ArsL'iiic 

]5ai'ium 

Calcium 

Carbon 

Chlorine , 

Cojiper (Cuprum) 

(lol(i (Aurum) 

IlYDROGiiN 

Iodine 

Iron (Kerrum)... 

Lead (Plumbum) 

Ma^t'sium 



Sym- 


Atomic 


bols. 


Weights 


Al 


l:i.e9 


Sb 


129. 


As 


75. 


Ra 


68.64 


Ca 


20. 


C 


6. 


CI 


3O..50 


Cu 


31.70 


Au 


9S.33 


11 


1. 


T 


120.36 


Fft 


28. 


Pb 


103.50 


Mg 


12.BT 



N.\MES. 

Manganepo 

Mercury (Hydrargyrum) 

Nickel 

Nitrogen, or Azote 

Oxygen 

Phopphorus 

Platinum 

l'ota.«,-.ium (Kalium) 

Silicium. or Silicon 

Silver (.\rgentum) 

Sodium (Natrium) 

Sulpbur 

Tin (Staisnum) 

Ziuc 



Weighls 



Mn 


27.07 


llg 


100. 


Ni 


29.57 


N 


U. 





8. 


P 


32. 


Pt 


9S.6S 


K 


39. 


Si 


21.35 


As 


108. 


Ma 


23. 


S 


16. 


Sn 


5S.S2 


Zn 


32.50 



In some books the atomic weights are given with reference 
to 0, taken as 100. Then II would be 12.50; C would be 
75; Hg 1200, etc. 



EQUIVA LENTS NOMENCLATURE. 51 

46. When we wish to indicate' that two substances com- 
bine, in the ratio of their atomic weights, we write their 
symbols together. Thus, HO denotes that hydrogen and 
oxygen are combined in the ratio of 1 to 8. FeS denotes 
a combination of iron and sulphur in the ratio of 28 
to 16. 

47. One substance may combine with another in several 
different laroportions ; but when this happens, it combines in 
the ratio of once, twice, or tliricc its atomic weights, or some 
other multiple of that weight. In such a case the symbol 
is written with a number either before or after it, showing 
how many times its atomic weight is to be taken. Thus, 
S, 2S, 3S, or S, S2, S3, indicate one, two, or three times the 
atomic weight of sulphur. FeS shows that Fe and S are 
combined in the ratio of 28 to 16 ; but FeSz shows that they 
are combined in the ratio of 28 to 32 (= 16 x 2). NO, 
NOsj, NO3, NO4, NO5, represent five different compounds of 
N and 0. In the first, these elements unite in the ratio of 
14 to 8; in the second, of 14 to 16; in the third, 14 to 24; 
in the fourth, 14 to 32, etc. 

48. The atomic weight of a compound is made up of the 
sum of the atomic weights of its constituent elements. For 
example, FeO is a compound of iron and oxygen, and repre- 
sents one atom of that compound. Its atomic weight, then, 
is 28 + 8 =: 36. SO3 is the symbol for sulphuric acid, a 
compound of one atom of sulphur united to three atoms of 
oxygen. Its atomic weight is 16 -f- 24 = 40. FeO and 
SO3 unite, then, in the ratio of 36 to 40, and form a com- 
pound having for its symbol FeO,S03. 

NOMENCLATURE. 

49. No one could possibly remember the names of all the 
various compounds he meets with, nor could he remember 
their composition, unless the name and composition were in 



52 NOMENCLATURE. 

some Tray associated. This lias been most liappily done by 
the system of naviing, first adopted by the French Academy 
of Sciences in 1787, and now in general use — modified only 
to suit the progress of science, and the languages of difibrent 
countries. In this system o^ noynaiclaiure, the more common 
substances which have been long in use are allowed to retain 
their old names ; as, iron, gold, sulphur, etc. Some newly- 
discovered elements have received names from some of their 
prominent properties; as chlorine, from cJiIoros, pale green, 
the color of the gas. So bromine, from hromos, referring to 
its bad odor. 

50. Two elements combined form a hinary compound; 
iliree a ternary; four a quarternary, etc. The names of 
such compounds are so constructed as to indicate their com- 
position. When oxygen combines with another element, the 
compound is called an oxide (unless it has acid properties); 
as, FeO, called oxide of iron ; CuO, oxide of copper ; CO, 
oxide of carbon. When a single atom of oxygen combines 
with another element, it is called the j^Totoxide j when there 
are two atoms of oxygen, it is called the deutoxide, or hin- 
oxide; when three, the tritoxide, or teroxide; as, PbO is 
protoxide of lead, Pb02 the deidoxide, etc. When there is 
one atom of to two or more of the other element, it forms 
a suboxide; as, CuaO, the suboxide of copper; and Pb20, 
the suboxide of lead. A sesquioxide is a compound having 
three atoms of oxygen to tico of the other element; as, 
FcaOa, the sesquioxide of iron ; AI2O3, sesquioxide of alumi- 
num. Peroxide indicates the highest degree of oxidation, 
next below the acid compounds of the same element; as, 
MnOi is the peroxide of manganese; and FcgOs is the per- 
oxide of iron. 

51. If we have compounds containing chlorine, bromine, 
or iodine, instead of oxygen, we call them chlorides, bromides, 
or iodides. AgCl is chloride of silver; and KI is iodide 



NOMENCLATURE. 53 

of potassium. Many compounds containing sulphur, j^hos- 
pliorus, and some otlier elements, have the termination -%iret 
to their names. CuS is suJj)huret of copper; FeS2 is hisul' 
plmret of iron. 

52. Many compounds containing oxygen are acids. These 
have their names from substances with which the is com- 
bined, with the terminations -ous and -ic. Thus, NO3 is 
nitroMs acid ; and NOg is nitri'c acid. The acid ending in 
-ic is stronger than that ending in -ous. Sulphur2c is a 
stronger acid than sulphuroi<s. 

53. When the oxides of the metals have such properties 
as cause them to unite readily with acids, they are called 
bases. The compound resulting from the union of an acid 
and hase is called a salt. The name of a salt is made up of 
the names of the acid and base of which it is composed — 
the acid giving the first, or generic, part of the name. When 
the acid name ends in -ic, the corresponding part of the salt 
name ends in -ate. Sulphuric acid forms sulphates. When 
the acid name ends in -ous, the salt name ends in -ite. Sul- 
phurous acid gives sulphfVes. KO is potassa. SO3 is sul- 
phuric acid. SO2 is sulphuroifs acid. Then K0,S03 is 
sulphate of potassa; and K0,S02 is sulpluYe of potassa. 

Where several acids contain different proportions of oxy- 
gen, the prefixes hyper and hypo are sometimes used — the 
former denoting above, and the latter below. For example, 
NO3, NO4, NO5, are nitrogen acids. The first is nitrous 
acid, the third nitric; and the second, coming between them, 
is usually called hypo-n\tviG acid, because it is below nitric 
acid in its oxidation. It might, with equal propriety, be 
called /t?/2jer-nitrous acid. The salts formed in the combi- 
nation of such acids with bases, retain the ^ame prefixes. 
Thus, hypo-nitric acid, with soda, forms what is called hypo- 
nitrate of soda. 
5* 



64 QUESTIONS. 

QUESTIONS ON CHAPTER III. 

^ 42. How many elementary substances are known ? Are many 
of them important? 

43. Why are symbols used ? Of what do they consist? For what 
do C, H, and Al stand? What if the substance has a Latin name? 
Of what are K, Sb, and Fe the symbols ? 

44, 45. What is an elementary substance? What is a compound? 
How do elementary substances always combine? In what propor- 
tion do H and combine in pure water ? The proportion of H and 
S in the gas of sulphur springs ? Why is H taken as the unit, or 
= 1 ? What are atomic weights ? Why are 28 parts of iron said 
to be equivalent, in chemical combination, to only 1 part of hydro- 
gen ? What are given in Table I ? 

46. How do we write substances, so as to indicate that they com- 
bine in the ratio of their atomic weights ? Explain the compound 
symbols, HO, FeS, KO, CaO, and NaCl? 

47. If one substance combines with another in several propor- 
tions, what is the law ? How are the sj'mbols then written ? Explain 
FeS, FeS2 ; NO, NO^, NO3, NO4, NO^. 

48. How is the atomic weight of a. compound made up ? Explain 
FeO and SO3; also FeO,S03. 

49. Would it be easy to remember the names of all chemical 
compounds? Why not? What system has been adopted to aid 
the memory ? How are common substances named ? Those newly 
discovered? 

50. What arc binary, ternary, and qiiarternary compounds ? What 
are oxides ? "What do FeO, CuO, and CO indicate ? What do you 
call PbO and PbOj; CugO and V\01 What are FcgOg and AI2O3 
called ? 

51. If a compound contains iodine, chlorine, etc. what name is 
given to it? Name AgCl, KI, and NaCl. When is the termination 
-uret used ? 

52. How are acids named ? Names of NO3 and NO5 ? What differ- 
ence between sulphurous and sulphuric acids ? 

53. What is a ia5«.? A sail? How named? How are //?//;«• and 
hypo used? Illustrate. 



OXYGEN. 55 



CHAPTER IV. 

METALLOIDS. 

54. Let us now examine the leading properties of the 
most important elementary substances, and of some of tlie 
compounds whicli they form by their various combinations. 

Of the elements given in Table I (§ 45), carbon, chlorine, 
hydrogen, iodine, nitrogen, oxygen, phosphorus, silicon, and 
sulphur, are usually regarded as non-metallic substances, or 
metalloids; while all others there given are regarded as 

metals.'^ 

OXYGEN {Si/mhol, 0; At. Wt. 8). 

55. This is the most important, as well as the most abun- 
dant, of the elementary substances. It enters into the com- 
position of almost everything we see around us. It constitutes 
I of the weight of water, about i of the air, a large portion 
of the substance of all rocks and soils, and is an abundant 
element in nearly all animal and vegetable substances. Hence, 
we take it first in order. 

56. The properties of oxygen may be best studied in con- 
nection with a few experiments. For this purpose it is most 
conveniently prepared from chlorate of j^ofassa, by the fol- 
lowing process. JSxj). Pulvei"ize an ounce of the chlorate, 
and mix with it about half-an-ounce of black oxide of man- 
ganese, (or fine, clean sand will do tolerably well instead of 
the manganese). Fill a large test-tube about two-thirds full 
of the mixture, and attach a bent tube to the mouth of it, 

* The distinction between metals and metalloids is not very defi- 
nite. Hydrogen, for instance, has more of the chemical properties 
of a metal, than are found in , senic. 



56 



OXYGEN. 



fitted air-tight by means of a cork, as in Fig. 12. Apply a 
spirit-lamp, moving the flame upward and downward along 
the tube a few times, to prevent it from breaking. The gas 
will soon begin to escape rapidly, and may be collected over 



Fig. 12. 




a vessel of water (a), in an inverted jar (h) — the jar being 
previously filled with water, and supported on a perforated 
shelf fixed in one side of the vessel, at such a height that 
it shall be covered to the depth of an inch or two by the 
water. A vessel thus arranged is called a pneumatic a'sfern, 
and may be in the shape of a box (or a fiih, which answers the 
purpose very well). This method is generally employed in 
collecting all gases which are not absorbed by water. Bot- 
tles with wide necks, and common fruit-jars, may be used as 
receivers in which to collect gases. 

Let us now see what change the heat has produced on the 
chlorate of potassa, so as to send off" oxygen gas. An atom 
of the chlorate has for its symbol, K0,C105 : when heated, 
the K and CI unite, and all of the oxygen escapes. The 
result is expressed thus : KCl + Oe, being one atom of 
chloride of potassium, and six of oxygen. The whole of the 
KCl remains in the tube with the manganese. 

67. Experiments. — 1. Fill three or four quart bottles or 
jars with oxygen gas at the pneumatic cistern. Slip them 
off" the shelf, with the mouths still inverted, into saucers or 



OXYGEN. 




small plates, witliout lifting tliem out of the water; and set 
them upon your table for further use. A little water around 
the mouth of the bottle or jar, as it stands inverted in the 
saucer, will prevent the gas from escaping. 2. Wrap one 
end of a piece of wire around the lower end of a short 
candle, and turn the straight part of the wire upward. Light 
the candle, turn up the mouth of one of your bottles of gas, 
and immerse the lighted candle into it (Fig. 13). Fig. 13. 
The candle will burn much more brilliantly than 
it did in the open air; and if blown out and re- 
turned to the gas with the smallest spark on the 
wick, it is immediately relighted. 3. Scoop out a 
small cavity in a lump of clialk, and suspend it by 
a piece of wire in the same way the candle was 
suspended, with the cavity turned upward, so as to form a 
little cup. In this place a lump of phosphorus half the 
aze of a pea, ignite it, and immerse it into a second bot- 
tle or jar of gas; and you will have a most dazzling light 
as the result. 4. Maku a, ooil of small iron or steel wire, by 
bending it around a tube or stick. Wrap a bit of twine 
around the lower extremity of the wire, and dip it into oil 
or melted tallow. Insert the upper end of the j'jq. 14. 
wire into a cork, fitted to one of your bottles 
(Fig. 14). Ignite the twine at the bottom of the 
coil, and let it down into the gas. The burning 
of the oiled twine will ignite the wire, and the 
coil will be rapidly consumed, throwing off sparks 
on all sides, and affording one of the most beau- 
tiful of our experiments. A watch-spring may be burned in 
the same way. 

From the foregoing experiments we conclude : (1) That 
oxygen is a colorless gas, not rapidly absorbed by water. 
(2) That bodies which burn in air, burn still more brilliantly 
in this gas. (3) That some bodies not easily burned in air, 




58 HYDROGEN. 

may be rapidly consumed in pure oxygen. If we weigh tliis 
gas, we shall find it a little heavier than air. 

58. The presence of oxygen in the air is necessary to 
support combustion, and also to sustain animal life; but our 
Creator has wisely and kindly diluted it with a harmless gas 
(nitrogen), which modifies its effects. If our atmosphere were 
pure oxygen, everything combustible on the earth would 
soon be consumed. Our blood, too, would become over- 
charged with the gas, and death would be the speedy result. 

For the effects of oxygen on decaying organic matter, see 
§147. 

HYDROGEN (S^mhoJ, II; At. Wf. 1). 

59. We have seen II set free by the galvanic battery 
(§ 40). It constitutes i of the weight of water, and forms 
an essential element in almost all animal and vegetable 
compounds. 

Experiments. — 1. Put a few fragments of zinc* into a 
common bottle with a wide neck, and fit to it a cork provided 
with two tubes — one leading to the pneuma- 
tic cistern ; the other, with a little funnel at 
the top, extending nearly to the bottom of 
the bottle (Fig. 15). A little water is to be 
poured into the bottle through the funnel-tube, 
until the lower end of the tube is covered. 
A little hydrated sulphuric acid (H0,S03) 
added, will be acted on by the zinc in such 
a way as to have its hydrogen set free. The first jxtrtions 
which pass over will be mixed with the air previously in the 
bottle, and should, therefore, be allowed to escape before the 
bent tube is placed under the receiver. The action of afiin- 

* Zinc melted and poured into cold water is divided into porous 
fragments (granulated), and is then in a good condition to be used 
in this experiment. 




HYDRO <; E N. 59 

ity between the Zn and HOjSOg may be expressed by a 
formula, thus : 

H0,S03 + Zn = ZnO.SOa + H. 

Here we see that Zn has taken the place of H in the 
sulphuric acid. Sulphate of zinc (ZnOjSOg) remains dis- 
solved in the water of the bottle. 2. Having collected 
several jars of the gas, lift one of them slowly from the 
shelf of the cistern, keeping the mouth down- 
ward. The gas, being much lighter than air, 
will remain in the jar. Insert a lighted candle 
into it, as in Fig. 16. A slight explosion will 
follow, whilst the gas will burn with a pale flame 
around the mouth of the jar. 3. Fill a tin tube, 
having a small hole near the closed end, about 
one-third full of H, and two-thirds full of air, and close the 
mouth of the tube loosely with a cork. A flame applied to 
the hole in the tube will instantly ignite the mixture, causing 
a loud report, and throwing the cork out with considerable 
force. 4. Put a handful of zinc fragments into a 
pint bottle (a) with a small neck, and adapt a piece 
of clay pipe-stem (6) to it with a cork (Fig. 17). Fill | 
the bottle half-full of a mixture of one part of sul- |& 
phuric acid with four or five of water. Insert the 




iv 



cork and tube, and after waiting a minute or two, till 
the air has been expelled by the gas, you may ignite ^| 
the jet of gas at the top of the tube: you then have 
the ^' philosopher' s candle." 5. Hold a cool, dry jar with 
its mouth just over the burning jet of H ; and the inner 
surface of the jar will soon be coated with a film of moisture. 
60. We infer, then: (1) That II is a colorless gas, not 
readily absorbed by water, and much lighter than a,ir. (2) 
That it explodes when mixed with air. (3) That when 
burned in air, the resulting compound is water. 



00 CARBON. 

01. Water. — Altliougli we say that water is composed of 
II and (and so it is, when perfectly pure), yet water free 
from foreign matter is seldom found in nature. Eain-water, 
T.'liicii is the purest, collects impurities from the air. Spring- 
water always has more or less of some soluble salts, carried 
out by it from the soils and rocks through which it has 
passed. 8ea-water contains several salts, of which common 
table-salt (chloride of sodium) is the most abundant. Medi- 
cinal springs owe their peculiar properties to substances dis- 
solved from the earth. The waters of many springs contain 
substances (such as salts of lime, ammonia, etc.) which are 
beneficial to soils; hence, meadows and fields watered by 
them are increased in fertility (§425). 

Seeds will not germinate, nor will plants grow, even in 
the best soil, without moisture. All the elements of nourish- 
ment received by the plant through its roots, must be dis- 
solved before the plant can absorb them. A supply of water 
is also necessary for the health and growth of animals. 

CARBON (Si/niLol, C; Af. Wt. 0). 

02. Carbon is one of the most important elements in 
nature. It constitutes the greater part of the solid matter 
of both plants and animals. It is the chief ingredient in 
FrG. 18. the vast beds of mineral coal deposited among the 

rocks of the earth. The diamond is the purest form 
of carbon. 

Bj:j)e7-hnenfs. — 1. Ignite a dry stick (i) (Fig. 18), 
and as it burns to a coal, slip the tube (n) over the 
burnt part. The air is thus cut oiF, and the combus- 
tion checked. The volatile matter burns out first, 
and the black residuum is nearly pure carbon. 2. 
Weigh a piece of charcoal recently extinguished, 
and, after exposing it in the air for several hours, weigh it 
asraia. It will be found to have increased in weight. This 



CARBON. 



61 





is owing to its absorbing air and otlier gases. 3. A piece 
of porous paper, like that on wliicli books and newspapers 
are printed, cut into a circular Fig. ly. 

form, a (Fig. 19), and folded 
by the lines which cross it, may 
be opened in the form h, and 
placed in the funnel c, so as to 
form its inner lining. Such an 
arrangement constitutes a filter. 
Into a half-pint of colored vine- 
gar stir a spoonful of finely- 
powdered charcoal ; put a little of the charcoal also in the 
filter ; then pour in the vinegar. As it trickles down from 
the funnel, it will be almost colorless. The charcoal has 
absorbed the coloring matter. Stagnant water may be ren- 
dered clear and sweet by a similar process. 

G3. Carhonic Acid (Si/mL. CO2). — Experiments. 1. 
Suspend a piece of ignited charcoal in a bottle of oxygen 
gas (§ 57), and it will be rapidly consumed. The oxygen 
combines with the carbon, and forms carbonic acid, which is 
a colorless gas. If the bottle has been corked 
while the charcoal was burning, a candle let 
down into it will be extinguished. 2. Put a 
handful of fragments of marble or limestone 
into the same bottle used in collecting hydro- 
gen (Fig. 15), and pour upon them a mixture 
of one part of sulphuric acid with five parts 
of water. The gas will escape with a brisk 
effervescence, and may be collected over warm 
water: cold water absorbs it rapidly. 3. It 
may also be conveniently collected in open 
bottles and jars, by the arrangement in Fig. 
20. The gas, being about one and a half times as heavy as 
air, sinks to the bottom of the receiver, and, gradually 
6 



Pig. 20. 




G3 CARBON. 

disiilacing the air, takes its place. 4. Stir a little freshly 
burnt lime into a bottle of water which has been recently 
boiled ; cork it, and set it aside until the excess of lime haa- 
settled, and the solution becomes perfectly clear. You then 
have " lime-water." Pour a little of it into a bottle contain- 
ing carbonic acid, and the solution at "once becomes turbid 
— carbonate of lime is formed. 5. Put a mouse or other 
small animal into a jar of this gas, and it will soon die. 6. 
Invert a jar full of it over cold water : in a few hours the 
water will have absorbed a considerable quantity of the gas, 
as will be seen by the rising of the water in the jar. 

64. The chemical changes which take place in the prepa- 
ration of CO2 from marble, may be represented in a formula, 
thus : 

CaO,CO, (marLIe) -f H0,S03 (su7j>h. acid) = CaO^SOj -f 
HO -f CO,. 

65. Natural Sources. — Combustion, respiration, and vol- 
canic action, are some of the chief natural sources of COj. 
It is formed abundantly in the burning of wood or coal — 
the carbon of the fuel combining with the ox;jgen of the 
air. During the decay of vegetable and animal substances, 
which is a slow combustion, this gas is abundantly generated. 
Hence its accumulation in old cellars and wells. During the 
breathing of animals, large quantities of CO, are thrown out 
into the air (see § 625). It also rises abundantly from many 
springs, ponds, lakes, etc. especially in volcanic regions. The 
air, thus continually receiving supplies of this poisonous gas 
(poisonous except in very small quantities), would soon be- 
come unfit to sustain life, had not Providence furnished one 
of those compensating arrangements so often met with in the 
study of nature. It is this : growing plants extract CO^ 
from the air. It is an important article of food for the 
plant. But while the plant consumes CO2, it gives out a 
fresh supply of oxygen. Combustion and respiration con- 



NITROGEN. 



63 



sume oxygen and generate carbonic acid, while vegetation 
consumes carbonic acid and generates oxygen; and thus 
the equilibrium of the air is preserved^ in respect to these 
gases. 

Carbonic acid is abundant in combination with different 
bases, as lime, potassa, soda, etc. forming a class of salts 
called carbonates. 



Fig. 21. 



NITROGEN, OR AZOTE (Sf/mhol, N; At. Wt. 14). 

66. Preparation. — This gas, as before stated, constitutes 
about I of our atmosphere. From this source it is most 
conveniently procured. A little metallic capsule, or a flat 
piece of chalk with a cavity in the top, may be placed on a 
flat cork, and thus made to float on the surface of the pneu- 
matic cistern. Place on this a little lump of phosphorus, 
ignite it, and immediately invert a 
jar over it, as in Fig. 21. The 
burning phosphorus consumes all 
of the oxygen within the receiver, 
and leaves the nitrogen. The water 
rises to take the place of the oxygen. 
The vapor of phosphoric acid, pro- 
duced by the burning phosphorus, 
will subside in a few minutes, and 
leave the nitrogen as a transparent, 
colorless gas, a little lighter than 
air. For experiments, it may easily be transferred to bottles, 
by inverting the bottles, filled with water, over the hole in 
the shelf of the cistern ; then slipping the mouth of the jar 
of gas beneath the shelf, and gradually turning it up, till 
the gas can escape, and pass up into the bottle. 

Experiments. — 1. Immerse a candle into a bottle of ni- 
trogen, and it goes out at once, from the want of oxygen. 
2. Place a small animal in a bottle of it, and it soon dies. 




G4 NITROGEN. 

The N is not poisonous to tlie animal, but death is caused by 
the absence of oxygen. 

The Atmosphere. 

67. Besides the mixture of and N, which constitutes the 
chief part of the atmosphere, small quantities of carbonic 
acid and other gases are found at every point accessible to 
man. > The atmosphere is also a great reservoir of moisture, 
as we have seen (§ 24). It is the great agency, too, by which 
the circulation of water on land is kept up. The vapor of 
water is continually rising and mingling with the air, and, 
by the mechanical agency of winds, is carried from those 
parts of the earth where evaporation goes on most rapidly; 
to those parts where rain is most needed. 

68. The atmosphere is one of the most important sources 
of nutrition for plants. If the air were deprived of moist- 
ure, all plants would wither, droop, and finally die. If car- 
bonic acid and ammonia were taken away, our crops would 
soon be starved. Carbonic acid, absorbed by the leaves, and 
taken up by the roots in rain-water, which brings down 
large quantities of it from the air, is the great source of 
carbon in plants. Ammonia, too, affords nutriment no less 
important. 

Nitrogen and Oxygen. 

69. Nitrogen forms several interesting compounds with 
oxygen, but only one of these is important for our jDresent 
purpose. This is nitric acid (NO5). 

Preparation. — Put three or four ounces of saltpetre 
(nitrate of potassa) into a retort (Fig. 22), and pour upon 
it an equal weight of sulphuric acid ; then apply heat gra- 
dually, by means of a spirit-lamp or charcoal furnace. The 
neck of the retort must pass into a receiver or bottle, kept 
cool by being immersed in cold water, or by having a wet 
cloth spread over it, on which cool water is made to drip 



NITROGEN. 



65 



continually. Tlie apparatus will at first be filled with red 
vapor, which is hyponitric acid, formed by the decompositioa 



Fig. 22. 




of the first portions of nitric acid. This, however, will dis- 
appear after a while, and the nitric acid be distilled into the 
cool receiver, and there condensed as a liquid, colored by the 
presence of nitrous or hyponitrous acid. When nitric acid 
is pui-e, it is a colorless liquid, about once and a half times 
(1.52) as heavy as water. 

Exjieriments. — 1. Put a drop of it on a piece of colored 
cloth : it will destroy the color, and finally corrode the mate- 
rial of which the cloth is made. 2. Pour a little of the acid 
upon some powdered charcoal heated red-hot in a cup or 
crucible ; brilliant combustion takes place. It will also 
ignite hot spirits of turpentine. 3. Dilute a little nitric 
acid with an equal quantity of water, and drop a fragment 
of copper into it. The copper will gradually disappear. It 
decomposes one portion of the acid, by taking away a part 
of its oxygen. This decomposed acid rises and forms the 
same red vapor in the air which we saw in the retort, when 
6* 



66 NITROGEN. 

preparing nitric acid. After tlie copper has become oxidized 
at the expense of one portion of the acid, it at once combines 
with another portion, and forms nitrate of copper (CaO,N05). 
The solution has a green color. 4. Pour a little of this 
solution into some clear water in a saucer : the water will 
scarcely be colored ; but add some ammonia-water (spirit of 
hartshorn), and you will have a beautiful blue color. This 
is one of the best tests for the presence of copper in a 
solution. 

Nitric acid combines with a great number of bases, giving 
us an important class of salts called nitrates. 

Nitrogen and Hydrogen. 
70. Ammonia (NH3). — This most valuable and interest- 
ing compound is not formed by the direct union of its two 
elements, under ordinary circumstances 3 but electricity will 
cause them to combine. This is supposed to take place high 
up in the air, u.nder the influence of lightning. By the sam 
agency, nitric acid is also formed by the union of N and 0; 
and this, combining with the ammonia, forms the nitrate of 
ammonia often found in rain-water. 

Prejyaration. — Put equal weights of slacked lime and 
Fig. 23. pulverized sal-ammoniac into a flask, and 

apply a gentle heat. A gas having a strong 
suffocating odor will be set free. The lime 
decomposes sal-ammoniac (NH4CI), thus : 
CaO + NH.Gl = CaCl + HO + NH3. It 
cannot be collected at the water-cistern, be- 
cause water absorbs it with great rapidity. 
A small cistern filled with mercury, instead 
of water, enables us to collect it readily; 
but if there is no mercury-cistern at hand, 
it may be collected, with tolerable success, in a bottle (Fig. 
23) inverted over the neck of the flask where it is generated. 




N I T R a E N. 



QT 



The gas, being much lighter than air, rises to the upper part 
of the bottle, and displaces the air. 

Experiment. — By attaching a bent tube to the mouth of 
the flask in which ammonia is generated (Fig. 24), and 



Fig. 24, 




causing the end of it to dip into a bottle of cold water, kept 
cool by surrounding ice, or by being set into a larger vessel 
of cool water, we can obtain the solution of this gas called 
" aqua ammoniae" 

71. Chemical Properties. — Ammonia is a strong alkaline 
base,* sometimes called "volatile alkali." It neutralizes the 
strongest acids, and, by its union with them, forms definite 
salts. But it is readily set free from its combinations by 
potassa or lime. 

Uxpcrimenf. — Eub a little sal-ammoniac and fresh lime 
together, and you may at once perceive the odor of the 
escaping ammonia. Ammonia is one of the most valuable 
ingredients in all animal manures, and every precaution 

■? * An alkaline base is any compound -wliich has a strong aiBnity 
for acids, and -which, ■when combined with them, forms salts. Po- 
tassa, soda, and lime are alkaline bases. 



G8 s u L p n u R . 

should be taken to prevent its escape. Hence, fresli lime 
sJiouId never be mixed with animal manures, because it seta 
the ammonia free. 

During the decay of many organic substances, such as 
dead animals and animal manures, ammonia is generated 
chiefly as a carbonate (NH40,C02), which is volatile, and will 
escape, unless in some way prevented. If gypsum in fine 
powder (ground plaster) is mingled with such manures, and 
water sprinkled freely over the heap, the gypsum, which is 
sulphate of lime (CaO,S03), will act uj)on the carbonate of 
ammonia in such a way that both compounds will be decom- 
posed. The sulphate of lime wall become the carbonate, and 
the carbonate of ammonia will become the sulphate. The 
carbonic and sulphuric acids exchange places. The sulphate 
of ammonia thus formed is not volatile, and hence the am- 
monia is said to be " fixed." But this sulphate is soluble ; 
and hence the manure should not be exposed to heavy rains 
before it is applied to the soil, else much of the ammonia 
will be washed out and lost. Every farmer should be fami- 
liar with the properties of ammonia, and its relation to other 
compounds; hence, we shall have more to say about it under 
the head of " Fertilizers." 

SULPHUR (S^nihol, S; At. Wf. 16). 
72. This is a well-known yellow, brittle solid, often called 
" brimstone." It is insoluble in water, but dissolves readily 
in hot spirits of turpentine. If heated in a test-tube to 
about 230°, it melts, forming a thin yellow liquid. When 
heated to a higher temperature, it gradually forms a thick, 
viscid mass, which will not run out of the tube when in- 
verted. At a still higher temperature, it again becomes 
more liquid, and may be poured into cold water. Thua 
cooled, it forms a soft, elastic mass, not unlike gum-elastic. 
At about 600° it begins to boil, and rises in the form of a 



SULPHUR. 69 

dense brown vapor, which condenses in the upper part of the 
tube as a fine yellow powder (flowers of sulphur). 

Sulphur is found abundantly in some volcanic regions, 
mixed with clay, ashes, and other impurities. From these 
it is separated by being distilled into large chambers, where 
it is condensed on the walls in tufts or clusters of fine yellow 
powder : these clusters are the flowers of sulphur. When 
melted and cast in wooden moulds, it forms roll sulplmr. 

73. Both plants and animals contain small quantities of 
sulphur. Plants find it in the soil in the form of sulphates. 
Animals derive it from the plants upon which they feed. It 
exists more abundantly in the hair than in any other part of 
the animal. It is the sulphur in black mustard and in eggs 
which tarnishes silver spoons — forming sulphuret of silver 
on the surface. 

Sulplixir and Oxygen. 

74. When sulphur is burned in the open air or in oxygen, 
it unites with two atoms of oxygen, and forms an acid gas 
(SO2) of very disagreeable odor. Exp. — Hold a rose, or 
any colored flower, over burning sulphur, and it will lose its 
color. A yellow straw treated in the same way will be whi- 
tened. This gas is used extensively in bleaching. It is 
called sulphurous acid. 

75. SuIpJiuric Acid This is the most important and 

valuable compound of sulphur and oxygen. It is a heavy, 
oily liquid, nearly twice as heavy as water. It was formerly 
obtained by heating sulphate of iron (green vitriol) to a high 
temperature, and distilling the oily acid from it; hence it 
derived its common name, " oil of vitriol." Its symbol is 
H0,S03. For the process by which it is now prepared, the 
reader is referred to the larger works on chemistry. 

Sulphuric acid has a strong affinity for water. This may 
be illustrated : 1. By leaving a weighed portion of it in an 
open glass vessel for a day or two. It will be found to haw 



70 CHLORINE. 

increased in weiglit, owing to the moisture absorbed from 
the air. 2. Fill a large test-tube one-third full of water; 
then fill it up quickly with sulphuric acid : the tube will 
become too hot to be held in the hand. The rapid combi- 
nation of the acid and water produces the heat. 3. A piece 
of wood dipped for a few minutes into strong sulphuric acid, 
is blackened (charred). The acid takes out hydrogen and 
oxygen from the wood, in the form of water, while the car- 
bon is left in an uncombined condition. 

7G. Sulphuric acid is used extensively in the arts. It is 
also valuable to the former. We shall hereafter (§ 378, <7) 
recommend its use for preserving ammonia in animal manures. 

With bases it forms sidpJiates. Gypsum is a sulphate of 
lime. Glauber's salt is a sulphate of soda. These are both 
valuable fertilizers. 

Sulj)hur and Hydrogen. 

77. The disagreeable gas which rises from sulphur springs, 
is a compound, of sulphur and hydrogen (IIS). It is usually 
called sidpliuretted hydrogen, or liydrosulphuvic acid. It is 
produced during the decay of eggs, and of many animal 
substances. When bright silver is exposed to this gas, it is 
soon tarnished, by the sulphur from the gas combining with 
the silver. 

CHLORINE {Symbol, CI; At. Wt. 35.5). 

78. Experiment. — Put an ounce of black oxide of man- 
ganese into a flask (Fig. 25), and pour upon it two liquid 
ounces (half a teaeupful) of muriatic acid. Stir up the 
mixture well, and let it stand a fevf minutes. A gentle heat 
from a lamp, or pan of coals, will cause a heavy green gas 
to pass over into the bottle (Z^).* This gas is nearly two 

«■ Mn02 + 2IIC1 = MnCl -f 2II0 -f CI. 



CHLORINE 



71 



Fig. 




and a half times heavier than air. It will, therefore, sink to the 
bottom of the bottle; and, by gradually filling it up, will dis- 
place the air entirely — ^just as water, poured into a bottle of oil_, 
would cause the oil to flow out, while 
the water alone would fill the bottle. 

79. This gas is called " chlorine," 
because of its green color. It can- 
not be collected over water, because 
water absorbs it freely. But over a 
hot solution of salt it may be col- 
lected, as this does not absorb it. 
This gas should not be inhaled freely, 
else it will irritate the throat and lungs. 

Experiments. — 1. A burning candle let down into a bottle 
of chlorine gas, burns but slowly, and gives off a dense 
smoke. This is because the chlorine combines with the 
hydrogen alone of the flame, while the carbon (for which it 
has no afiinity) is set free in the form of smoke. 2. A frag- 
ment of phosphorus suspended in this gas takes fire sponta- 
neously. 3. Suspend in chlorine a moistened strip of paper 
on which there is writing done with common ink, and the 
writing will soon disappear. This is owing to the strong 
afiinity between chlorine and iron. The iron, which gives 
the black color to ink, is removed by the chlorine, and the 
color thus destroyed ; while the new compound of chlorine 
and iron is colorless. 

80. Chlorine is one of the elements in common salt, which 
is chloride of sodium (NaCl). It is found in small quanti- 
ties in nearly all plants, and quite abundantly in sea-weeds. 
In the fluids of animals it is found in considerable abun- 
dance. The compounds of CI with the metals are called 
" chlorides." 

Chlorine and Hijilrogen combine and form a strong acid. 
When free, it is a gas ; but a solution of it is generally sold 



72 i?nosrii ORU s. 

by druggists 'undei* the name of " mui'iatic acid." It is a 
cheap acidj and niay be employed in preserving manures 
(§378, cZ). 

Iodine, Fluorine, and Bromine resemble chlorine in most 
of their chemical properties and relations. 

PHOSPHORUS {Si/mhol, V ; At. Wt. 32). 

81. This remarkable substance is obtained from bones. 
When freshly prepared, it is a transparent, waxy substance, 
generally bought in the form of round sticks. A stick of 
it, placed in a tube, covered with water, and exposed to the 
light of the sun a few days, becomes brown. The light 
seems to cause some rearrangement of its atoms, without any 
essential change of its properties. 

82. Phosphorus has a very strong affinity for oxygen. If 
exposed to the air it undergoes slow combustion, gives off a 
white vapor, and in the dark emits a faint light. It takes 
fire from a slight elevation of temperature, or from friction ', 
hence its value in making friction matches. It must be kept 
under water, to exclude it from the air. It must be handled 
cautiously, lest it be ignited by the heat of the hand. Burns 
produced by it arc exceedingly painful. In its free condi- 
tion, as well as in some of its compounds, phosphorus is very 
2ioisonous. 

83. When ignited in the open air or in oxygen gas, phos- 
phorus combines with five atoms of 0, forming phosphoric 
acid (PO5). This acid forms a very important class of salts, 
called " phosphates." Phosphate of lime is the white sub- 
stance left when a bone is burned in an open fire. It forms 
a large proportion of the bones of all animals. Phosphates 
also exist in other parts of animals, and in different parts of 
plants, but especially in the seeds. 

For a more full description of the phosphates, we must 
turn to the bases with which phosphoric acid combines. 



V 



SILICON — BORON. 73 

SILICON (^Symhol, Si; At. Wt. 21). 

84- This substance possesses but little practical interest, 
except in its combination with oxygen. 

Silica (SiOs) is a very abundant mineral, found in nearly 
all the rocks and soils on the surface of the earth. We often 
find it in beautiful crystals, having the form of six-sided 
prisms with six-sided pyramids at the ends (Fig. Fig. 26. 
26). Flint and sand are nearly pure silica, but /h. 
often colored with a little of the oxides of iron ^^-A^ 
and other metals. Agate, carnelian, amethyst, 
opal, and some other gems, are composed of silica. 
The strongest acids will not dissolve nor decom- 
pose silica. It is also so hard as to scratch glass readily, and 
is very infusible alone. 

Although silica is so very hard, insoluble, and tasteless, it 
is classed among the acich, and called " silicic acid." It is 
regarded as an acid, because, when heated to a high tempe- 
rature with potassa, soda, or lime, it combines readily with 
these bases, and forms a class of salts called '^ silicates." 

The stalks of grains and grasses contain considerable 
quantities of silica (§ 185). It must, therefore, be found in 
a soluble form in every fertile soil. 



BORON {Symbol, B; At. Wt. 11). 

85. The only interesting compound of boron is boracio 
acid (BO3). In combination with soda, this acid forms the 
horax used in the arts : it is a borate of soda. Borax is used 
as a flux for cleaning the surfaces of metals, and for excluding 
the air in welding and soldering with hard solder. It forms 
a thin and very fusible film over the surface of the metal, 
and thus prevents oxidation, until the two surfaces to be 
united can be brought together. 
7 



74 QUESTIONS. 



QUESTIONS ON CHAPTER IV. 

§54. Subject of this chapter? Which are the metalloids of 
Table I? 

55, 56. Symbol and atomic weight of Oxygen'? Is oxygen im- 
portant? Abundant? Where found? From what most conve- 
niently prepared ? Explain the process. Describe the apparatus 
in Fig. 12. Use of its different parts? What changes take place in 
KOjClOg in the preparation of oxygen ? 

57. Detail the fii'st experiment here given; the second; the third; 
the fourth. What is the first conclusion drawn from these experi- 
ments? the second? the third? 

68. AVhy is oxygen necessary in air? What advantage from 
being mixed with nitrogen ? What if our atmosphere were pure 
oxygen ? 

59. Symbol and atomic weight of Hydrogen? In what comj^ounds 
is it found? How prepared? Explain formula HOjSOg -j- Zn =■ 
ZnOjSOg -|- H. Explain experiment second. How may a mixture 
of hydrogen and air be exploded ? Is hydrogen combustible? How 
illustrated ? Product of the combustion ? 

60. First inference drawn ? second? third? 

61. Of what is water composed ? Is it generally pure ? Its purest 
form? What does spring-water always contain? Sea-water? Ee- 
lation of water to the growth of plants? 

62. Symbol and atomic weight of Carbon? AVhy important? 
Various forms? First experiment? What does it illustrate? Se- 
cond experiment ? third ? How may stagnant water be purified with 
charcoal? 

G3, 64. What is carbonic acid? First method of preparing it? 
Second method? Why collected over warm water? Why in open 
bottles ? How is lime-water prepared ? How affected by carbonic 
acid ? Experiment with a mouse ? Explain the chemical changes 
in its preparation from CaOjCOj. 

65. What are the natural sources of COj? How formed by com- 
bustion? by decay? by breathing? Why is not the quantity in the 
air increased ? 

66. Symbol and atomic weight of Nitrogen 7 Hoav much of it in 



QUESTIONS. 75 

tbe atmosphere? How procured for experiment? Explain Fig. 21. 
Experiments first and second? 

67, 68. AVbat are tlie constituents of tlie Atmosphere? How does 
the air cause circulation of moisture ? What relation does it bear to 
plants ? What does it provide for their nourishment ? 

69. What is the most important compound of nitrogen and oxy- 
gen? How prepared? Its properties? First experiment with NOg? 
second? third? What is the product ? Fourth experiment ? What 
are nitrates ? 

70. What compound does nitrogen form with hydrogen? Its sym- 
bol ? Do its elements generally combine directly ? How prepared ? 
Explain the process. Can it be collected over water ? Experiment 
illustrated in Fig. 2-1 ? 

71. Chemical properties of ammonia? Its effect on acids? IIow 
is it readily set free ? Experiment. Why should lime not be mixed 
with animal manures? When is carbonate of ammonia generated? 
How is its escape prevented ? Explain the chemical action between 
carbonate of ammonia and gypsum. 

72. Symbol and atomic weight of Sulphur ? Its form and proper- 
ties? Influence of heat upon it? What are flowers of sulphur? 
Where is sulphur found? How purified ? 

73. Is it found in plants and animals ? Whence do they obtain 
it ? In what part of the animal is it most abundant? Why do eggs 
tarnish silver spoons? 

74. Product of sulphur burnt in open air ? Experiment with SO2? 
What isSOa? 

75. Describe sulphuric acid. Its symbol? AflSnity for water? 
First experiment ? second ? third ? 

76. Uses of sulphuric acid ? What are sulphates ? Examples. 

77. What compound of S and H is mentioned? AVhat is it 
called ? 

78. 79. Symbol and atomic weight of Chlorine ? How prepared ? 
Why collected in an open bottle? Why called "chlorine" ? Expe- 
riment fii-st ? second ? third ? 

80. Wh-At is common salt? What are chlorides ? What compound 
does CI form with H ? Its properties ? 

81. Symbol and atomic weight of Phosphorus? Its source? Pro- 
perties ? Influence of light upon it ? 

82. 83. Its aflinity for oxygen? How illustrated? For what 



76 QUESTIONS. 

used? How is phosphoric acid formed? The most importaut 
phosphate? 

84. Symbol and atomic weight of Silicon? Its only important 
compound with oxygen ? Forms under which it occurs ? Its pro- 
perties ? Why regarded as an acid? What are "silicates"? In 
■what part of plants is silica abundant? 

85. Symbol and atomic weight of Boron ? What valuable com- 
pound ? What is borax ? For what used ? Why ? 



METALS, 



CHAPTER V. 



METALS, 



86. There are about fifty metals known to chemists, but 
only a few of these are important to our present purpose. 
These we will briefly describe. They are generally found 
in the earth, combined with other substances in the form of 
ores. A few of the metals, such as gold and silver, are 
often found uncombined, and are then called native metals. 
Oxygen, sulphur, chlorine, and some of the acids, are the 
substances with which the metals are generally combined in 
ores. 

With oxygen some metals form both oxides and aeids. 
Thus, FeO and FcjOs are both oxides of iron ; but FeOs is 
''ferric acid." So, CrO and Cr02 are oxides of chromium; 
whilst CrOs has strong acid properties, and is called " chromic 
acid." 

With sulphur the metals form sulpliurets : FeS, KS, and 
SbS.2 are sulphurets of iron, potassium, and antimony. With 
chlorine they form such chlorides as NaCl (chloride of so- 
dium), AgCl (chloride of silver), etc. 

The oxides of the metals nearly all combine with acids, 
and form what are called "salts" of the metals. The pi'ot- 
oxide of iron combined with sulphuric acid forms the salt 
(FeOjSOs) called sulphate of iron. So, ZnO,S03 is sulphate 
of zinc ; KOjNOj is nitrate of potassa; and CaO,C02 is car- 
bonate of lime. 

87. Alkalies. — Potassa and soda (KO and NaO) were 
formerly the only substances called alkalies ; but that term 

7* 



78 POTASSIUM. 

is now frequently used in a -wider sense, and applied to other 
bases whicli have a strong affinity for acids. Lime, magne- 
sia, and other compounds of similar character, are regarded 
as alkaline bases.* 

POTASSIUM {Si/mhol, K; At. Wt. 39). 

88. This is a metal so soft that it may be moulded to any 
shape with the fingers, and so light that it will float on the 
surface of water. Exp. — Drop a little lump of potassium 
upon the surface of a cup of water : it will at once take fire, 
and float about over the surface until it finally disappears. 
The affinity of the potassium for oxygen is so strong, that 
the oxygen is rapidly taken from a portion of the water, while 
the hydrogen is set free. The heat generated by the rapid 
union of the potassium and oxygen is sufficient to ignite the 
liberated hydrogen. The flame thus produced is tinged by 
the potassium with a purple hue. The water will have oxide 
of potassium in solution. When evaporated to dryness, a 
white mass remains, which is oxide of potassium (potassa) 
combined with one atom of water (HO,KO). This combi- 
nation is called " hydrate of potassa." 

89. Carbonate of Potassa (K0,C02) exists abundantly in 
wood-ashes. It is the substance which gives strength to lye. 
It is found in the ashes of nearly all plants ; hence potassa 
must be an abundant element in the vegetable kingdom. 
Exj). — Mix half-a-pound of ashes from wood, with a quart 
of hot water, and after stirring the mixture for a few minutes, 
pour it upon a paper filter (see Fig. 19) ; then evaporate the 
water to dryness in a saucer. The solid matter left in the 
saucer will be the carbonate of potassa, dissolved out of the 
ashes by the water. 

90. Nitrate of Potassa (Saltpetre). — E:q). Pour a little 

* For an explanation of the term "alkaline base," see ^ 71, twle. 



SODIUM. 79 

water upon tlie carbonate of potassa obtained by the last 
experiment; then add nitric acid, drop by drop. It will be 
seen that bubbles of gas escape as soon as the nitric acid 
mingles with the solution : these bubbles are carbonic acid. 
The nitric acid combines with the potassa, setting free the 
carbonic acid, and forming a new salt (K0,N05), nitrate of 
potassa. If the solution is again evaporated nearly to dry- 
ness, and set aside to cool, it will deposit crystals of nitre. 
This valuable salt is used extensively in making gunpowder, 
in the preservation of meat, and in preparing nitric acid. It 
is a powerful fertilizer on nearly all soils, but is too costly to 
be generally used in that way. 

91. Sulphate of Potassa (KOjSOj) is formed when sul- 
phuric acid is added to a solution of potassa, or of carbonate 
of potassa. 

92. Chlorate of Potassa is the salt we have used (see 
§ 56) in preparing oxygen gas. There are many other salts 
of potassa which we must pass by for the present. 

SODIUM {Symbol, Na; At. Ys^'t. 23). 

93. Sodium is very much like potassium in all of its pro- 
perties. It is a little heavier, but still light enough to float 
on water. It combines rapidly with the oxygen of the water, 
but gives out less heat. It will not cause ignition unless 
confined to one place on the water. Oxide of sodium (NaO) 
is the base of all the salts of soda. 

94. Chloride of Sodium (NaCl) is our common table-salt, 
and is the most abundant, as well as the most important, of 
all the compounds of sodium. It is often found in beds of 
"rock-salt" in the earth, but is most commonly obtained from 
the water of salt springs, and of the ocean. 

95. Sulphate or Soda is prepared on a very large scale 
by heating together common salt and sulphuric acid (NaCl -(- 
HOjSOs == HCl -f NaOjS jj. Hydrochloric acid is thus set 



80 CALCIUM. 

free, and when collected in water forms "muriatic acid." 
Sulphate of soda often passes under the name of " Glauber's 
salt." It is a cheap article, and may be employed to great 
advantage as a fertilizer. 

96. Carbonate of Soda (NaOjCOa). — This useful salt is 
prepared by decomposing the sulphate, by means of heat, and 
a mixture of sawdust and carbonate of lime. The hkarhonatc 
or supercm-bonate of soda is formed by passing a current of 
carbonic acid gas through a strong solution of the carbonate, 
or by passing the gas over a moist mass of the carbonate. 
The bicarbonate is used extensively in making bread. When 
mingled with a mass of dough, together with cream of tar- 
tar, sour milk, or some other acid substance, the carbonic 
gas is set free by the acid used, and little bubbles of gas are 
formed at all points throughout the mass of dough. In the 
process of baking, these bubbles are greatly expanded by the 
heat, and the bread is thus rendered porous, or " light." 

97. Nitrate of Soda abounds on the coasts of Peru, and 
is exported to other countries, and employed in the manufac- 
ture of nitric acid. The acid is set free by the action of 
sulphuric acid (see § 09). The sulphate of soda, Avliich is 
generated by the operation, is a valuable fertilizer. 

98. When soda salts abound in a soil, they often take the 
place, to some extent, of potassa salts, in plants growing upon 
that soil. The same species of plant near the shore, where 
the spray of sea-water is blown over the land, generally has 
more soda and less potassa than it has when it grows far in- 
land. We may often observe this fact in the different ana- 
lyses of ashes of the same grain from different localities. 

calcium {Si/mlol, Ca; At. Wt. 20.5). 

99. Metallic calcium (the base of lime) is not easily pro- 
cured, and possesses no practical interest. But its compounds, 
known as lime and salts of lime, are of the highest import- 



CALCIUM. 81 

ance, both, in the arts and in agriculture. It exists most 
abundantly as carbonate of lime (CaO,C02)3 in the forms 
of common limestone, marble, chalk, etc.; and as gypsum, 
or sulphate of lime. 

100. Lime (CaO). — Exjjs. 1. Throw a few fragments of 
limestone or chalk into a fire of wood or charcoal, where they 
may be tept at a bright red heat for several hours. The 
carbonic acid will be expelled, and quick-lime will be left. 
2. Weigh a few of these fragments of lime carefully, then 
pour over them slowly about one-third of their weight of 
water ; the water will be rapidly absorbed, the lime will be- 
come quite hot, and soon crumble to a dry, white powder. 
The water has combined with the lime, and assumed a solid 
form. This is called "hydrate of lime" (HO,CaO), with 
reference to its having water combined with it. It is said 
to be "slaked" with reference to the same fact. It is 
also called "' slacked lime " from the fact of being reduced 
to a fine powder. The term " caustic lime " is applied 
to it, because of its corroding influence on vegetable and 
animal substances. The water absorbed by lime in slack- 
ing, increases the weight by about one-third of the weight 
of the newly-burnt lime. This fact is of importance in 
buying lime by weight. 3. Expose a portion of stone lime 
(unslacked lime) to the open air for a few weeks, and 
it will absorb moisture from the air ; but in the meantime 
it will also absorb carbonic acid, and will be converted 
again into carbonate of lime. Such lime is said to be " air- 
slacked." It is also called " mild lime," or " weak lime," 
because the carbonic acid has destroyed its caustic character. 
When thrown into an acid, it effervesces. Caustic lime spread 
on a field, and left exposed upon the surface, soon becomes 
changed to a carbonate. 4. Rub a little caustic lime and sal- 
ammoniac together in a cup or mortar, and the odor of am- 
monia will at once be perceived. Such will be the case, too, 



82 CALCIUM. 

if any other salt of ammonia, or even a little guano, is treated 
in the same way with caustic lime. This property of lime 
shows that it should never be mixed with manures which 
contain ammonia, because the ammonia, the most valuable 
ingredient, is thus expelled. The use of lime as a fertilizer 
will be discussed in a subsequent chapter. 

101. Mortar. — "A mixture of lime and sand, on exposure 
to the air, gradually forms into a hard, stony mass. This 
consolidation is to be ascribed to three causes : 1st. The water 
evaporates, and the hydrate of lime remains behind as a co- 
hesive mass ; 2d. The lime attracts carbonic acid from the 
air, and there is formed a mixture of hydrate of lime and 
carbonate of lime, which possesses greater firmness than either 
body separately; 3d. On the surface of the sand a chemical 
combination is gradually formed of the silicic acid with the 
lime, both becoming, as it were, incorporated together. This 
explains the remarkable hardness of mortar in old buildings." 
— Stockhardt. 

102. Carbonate of Lime constitutes the common lime- 
stones, marbles, and chalk so widely scattered over the earth. 
It is found in the various forms of marl, and is a constituent 
of all good soils. The carbonate may be distinguished from 
other salts of lime by its eflfervescing when an acid is poured 
upon it. Water charged with carbonic gas has the power 
of dissolving carbonate of lime : it then becomes '' hard 
water." The water which issues in springs from limestone 
rocks, always has carbonate of lime dissolved in it, and is 
called " limestone-water." When such water is boiled, the 
carbonic acid is expelled, and the carbonate of lime is set 
free as a white powder. This forms incrustations on the 
inner surface of tea-kettles, steam-boilers, and other vessels 
in which limestone-water is boiled. The stalactites which 
hang from the roofs of caves are carbonate of lime, which 
has been deposited by the water dripping from the roof. 



C A L C I U M. 83 

Carbonate of lime is often beautifully crystallized in white 
or transparent crystals. 

103. Gypsum (Sulphate of Lime) is an abundant mine- 
ral, found in extensive beds in many parts of the world. It 
often occurs in transparent, flat crystals, and is then called 
" selenite." When very compact and white, it is called " ala- 
baster." It is slightly soluble in water, requiring about 500 
parts of water for its solution. Gypsum passes also under 
the name of '' plaster." Its composition is shown by this 
formula : CaOjSOg -f 2 HO. When heated to two or three 
hundred degrees, the two atoms of water are expelled, and 
it becomes CaOjSOs, which is " plaster of Paris," or " cal- 
cined plaster." 

Experiments. — 1. Heat a few ounces of ordinary ground 
plaster in an iron vessel, stirring it constantly, until moisture 
will not be deposited on a clean, cool piece of glass held over 
it; taking care not to let the heat rise much above oOO° F. 
You now have some calcined plaster. 2. Wind a narrow 
strip of paper around a piece of money, so as to make a little 
paper-box, of which the coin shall form the bottom. Mix 
your calcined plaster with water, so as to form a paste. Fill 
the paper-box with this paste, and set it aside for an hour or 
two : you will then find it to have become so hard, that you 
can unwrap the paper, and remove the coin. The face of 
the coin will leave a reversed impression on the plaster. This 
illustrates the formation of plaster casts. Calcined plaster 
is said to "set" with water. The water combines with it 
like water of crystallization, and thus forms a solid mass. 

Gypsum is well known as a valuable mineral fertilizer, to 
which we shall frequently allude hereafter. 

104. Phosphate of Lime is found as a mineral in some 
parts of the world ; but its most abundant source is in the 
earthy matter of bones. When a bone is burned for a little 
while in a hot fire, it becomes white and brittle. This white 



84 BARIUM JI A a N E S I U M. 

substance is chiefly phosphate of lime (oCaO^POj). For its 
use see § 405. 

105. Nitrate of Lime is found with clay in the bot- 
toms of many caves. The soils in some places, too, abound 
in this salt. If lime is mingled with a mass of decaying 
animal and vegetable matter, it is converted into the nitrate 
of lime; The nitric acid is generated in the presence of a 
strong base, like lime, by the oxidation of the nitrogen of 
ammonia from the decaying matter, or the nitrogen of the air 
confined within the porous mass. 

Silicate of Lime. — This salt of lime is one of the consti- 
tuents of several varieties of rock, especially what are called 
" trap rocks." It is formed in variable quantities during the 
burning of lime. This process, and its value in the soil, are 
discussed under " Mineral Fertilizers." 

barium (Symbol, Ba; At. Wf. 68.6). 

106. The oxide of barium (BaO) resembles lime in some 
of its properties. The chloride (BaCl) is used by chemists 
to detect the presence of sulphuric acid in solutions. Uxp. 
— Dissolve a few grains of sulphate of soda in water, pour in 
a few drops of muriatic acid, and then add a little of the 
solution of chloride of barium : a beautiful white precipitate 
of sulphate of barita will be formed. 

Sulphate of Barita, called " barites," has been used as a 
substitute for gypsum on grass lands, with some success. It 
is used also for adulterating white paints. 

MAGNESIUM {Symbol, Mg ; At. Wt. 12). 

107. Magnesia (MgO) is the oxide of magnesium, and 
forms compounds, some of which resemble the corresponding 
salts of lime. Calcined magnesia is formed by heating the 
carbonate red hot, and thus expelling the carbonic acid. 
Carbonate of magnesia frequently occurs in combination with 



ALUMINUM. 85 

the carbonate of lime, in limestone rocks. It is also found 
in nearly all soils. Epsom sails, so much used as a medicine, 
is the sulphate of magnesia. Silicate of magnesia forms the 
mineral called " talc," and enters largely into the composition 
of serpentine and other minerals. 

108. Magnesia is found in the ashes of nearly all plants. 
It is, therefore, an important element of fertility in the soil. 
But soils generally have a sufficient supply of it, and hence 
its compounds are not often sought after as fertilizers ; though 
the sulphate has sometimes been applied with decided benefit. 
An excess of magnesia, in some forms, is regarded as inju- 
rious to soils. This is especially true of the caustic magne- 
sia, often formed in abundance, with caustic lime, from such 
limestones as abound in carbonate of magnesia. 

ALUMINUM {Si/mhol, Alj At. Wt. 13). 

109. Aluminum has recently been separated from its com- 
pounds in considerable quantities, and is found to possess 
such properties as will probably make it a useful metal. 

110. Alumina (AI2O3) is the only oxide of this metal 
known. In combinations with silica it forms clay, and also 
a large proportion of some of the most important minerals, 
such as mica and feldspar. 

111. Clay is a silicate of alumina,* and possesses the 
highest interest with the farmer. Its purest forms are pipe- 
clay and porcelain-clay. In soils it exists in widely differ- 
ent proportions. Some sandy soils contain no more than 8 
or 10 per cent of clay; and from this they vary to 50 per 
cent, and still have a sandy texture. As the quantity in- 
creases, the soil becomes more and more tenacious. 80 or 90 
per cent of clay makes a stiff clay soil. 

Clay absorbs water freely, and retains it firmly. When 

* Formula for clay : AlgOjjoSiOg. 



86 IRON. 

wet, it forms a compact, tenacious mass, and when dried 
"becomes very hard; hence the difficulty of cultivating stiflf 
soils. If sand be mingled with the clay in proper pro- 
portions, the texture of the soil is greatly improved (see 
§335). 

112. Clay is found in many rocks combined with other 
silicates, such as the silicates of lime, potassa, and soda. 
Rain and frost reduce such rocks slowly to small fragments, 
and these again are decomposed by atmospheric action, and 
by the silicates of potassa and soda being gradually dissolved 
out. The remainder is clay. 

113. Alum* is a double sulphate of alumina and potassa, 
combined with 21 atoms of water. The water may be driven 
off by heat, and the remaining porous mass is huTnt ahim. 
Exp. — Dissolve 5 ounces of alum in a half-pint of boiling 
water, and set it aside in a saucer to cool. When cold, the 
bottom of the saucer will be lined with a coating of beautiful 
crystals. 

IRON {Fcrrum), (Si/mlol, Fe; At. Wf. 28). 

114. Although gold and silver are sought after with so 
much eagerness, they are not half so important to man as 
iron. Fortunately for our race, this most valuable metal is 
also the most widely diffused of all the metals used in the 
arts. Our Creator has so placed it, that, with the proper 
exercise of industry and skill, man, in all lands, may supply 
himself with it in abundance. Prof. Stockhardt says : " It 
is the only metal which is not injurious to the health — the 
only metal which forms a never-failing constituent of the 
body, especially of the blood — the only metal, finally, which 
is found everywhere on the earth, in all stones and soils, and 
in almost every plant. Although we are ignorant wherein 

* Alum = KOjSOa + AljOj^SSOg -j- 2-lHO. 



IRON. 87 

consists the influence wliicli it exercises upon the life of ani- 
mals and plants, yet its universal diffusion must lead us to 
conclude that it has pleased the Highest Wisdom to invest 
iron with an importance for organic life, similar to that pos- 
sessed by comuion salt, lime, phosphoric acid, and some other 
substances." 

115. We find the iron used in the arts under several dif- 
ferent forms. 1. Cast-iron is the crude iron obtained by 
heating in large furnaces a mixture of some ore of iron with 
coal and limestone. The carbon and lime together remove 
nearly all of the substances combined and mingled with the 
ore ; while the metal, set free in a melted condition, runs to 
the bottom of the furnace, and is there drawn off". In making 
the finer kinds of castings, the iron from the furnace is re- 
melted in foundries, from which it is poured into moulds of 
various shapes. Cast-iron is much more fusible than the 
purer bar-iron ; hence its value for making stoves, ploughs, 
and a thousand other articles. The fusibility of iron is in- 
creased by the presence of a small quantity of carbon. In 
passing through the furnace, the iron combines with a por- 
tion of the carbon used in separating it from the ore. This 
not only makes it more fusible than pure iron, but also makes 
it brittle. 

2. When articles such as rakes and forks are made of cast- 
iron, and then kept red hot for several days in contact with 
an oxide of iron, the carbon is nearly all removed from them, 
and they become soft and flexible. The metal thus treated 
is called " malleable cast-iron." 

3. Bar-iron is formed by burning the carbon out of cast- 
iron, in a forge-fire, and then hammering it into bars. It 
may then be passed between heavy rollers, and formed into 
slieet-iron; or drawn through holes in steel bars, and formed 
into wire. 

4. Steel is prepared by embedding bars of iron in pow- 



68 I R N. 

dered charcoal, and keeping it heated to redness for some 
time. Tlie iron combines with some of the carbon of the 
coal, and is thus rendered both harder and more fusible. 
"When bars thus prepared are melted and cast in moulds, 
they form cast-steel. 

116. Iron and Oxygen. — At ordinary temperatures 
iron combines readily with the oxygen of the air, if moist- 
ure be present, and the result is " rust." At a red heat the 
surface of a piece of iron soon becomes coated with an oxide 
of iron. We have seen (§ 57) how rapidly ii'on may be con- 
sumed in pure oxygen gas. Ex^). — Sprinkle some fine iron 
filings into the flame of a spirit-lamp, or hold a piece of iron 
over the flame, and rub the metal with a file, so that the small 
fragments cut ofi" will fall into the flame : they will take fire, 
and burn with the appearance of bright sparks. 

117. The protoxide (FeO) is the base of most of the salts 
of this metal. This oxide cannot be obtained in a separate 
form, on account of its strong affinity for an additional quan- 
tity of oxygen, by which it is changed to the sesquioxide 
(FcaOs). The sesquioxide is also the base of several im- 
portant salts of iron. The brown sediment we find about 
chalybeate springs is FszOg, with an atom of water (HO,Fe203). 
The sesquioxide of iron is often called "peroxide:" it is 
found in the earth in vast deposits, and is regarded as one 
of the most valuable ores of this important metal. It is the 
chief coloring matter in rocks and soils, except in cases 
where organic matter abounds, as in many limestones, and 
in dark alluvial soils. The red and brown varieties of clay 
are colored with this oxide. Oxide of manganese is, how- 
ever, frequently associated with oxide of iron. 

Black Oxide or Iron, called " magnetic oxide," seems 
to be a combination of protoxide with peroxide ; the formula 
being, FeOjFe.Os. The black, scaly particles which drop 
from the surface of iron, as it is wrought with the black- 



IRON. 89 

smith's hammer, are composed of this oxide. When found 
as a mineral, it has the property of being attracted by the 
magnet; and many masses of it are native magnets, or 
" load-stones." 

118. Salts of the Oxides of Iron are numerous, but 
we can notice only a few. 1. Carbonate of iron (FeO,C02) 
is one of the most valuable ores, and is often found beau- 
tifully crystallized ; and hence called " sparry iron-ore." 2. 
The sulphate (FeO,S03), called "copperas" and "green 
vitriol," is the most common salt of iron, and the one most 
extensively used in the arts. It is a crystalline salt of a 
green color, and very soluble in water. Its preparation is 
given in § 119. In the manufacture of ink, and in dyeing 
black colors, it is extensively used. Its use in agriculture 
will be mentioned in connection with fertilizers. 

119. Iron and Sulphur. — When sulphur unites with a 
metal without oxygen, we call the compound a " sulphuret." 
There are several sulphurets of iron. The protosulphuret 
(FeS) is formed when sulphur and iron filings, or tacks, are 
heated together in a covered crucible (§ 5). It is used in 
preparing sulphuretted hydrogen. 

Bisulphuret of iron is commonly called "pyrites," or 
"iron pyrites" (FeSg). It is a very abundant mineral, and 
occurs in beautiful yellow crystals, in the form of cubes and 
octohedrons. Because so many people suppose, when they 
discover it in the rocks, that they have found gold, it has 
received the significant name of " fool's gold." When heated 
to a high temperature, the bisulphuret of iron parts with a 
portion of its sulphur, which may be collected in the form 
of " flowers of sulphur." The iron still remains combined 
with a portion of the sulphur ; and if exposed to air and 
moisture, the sulphur and iron both unite with oxygen. The 
sulphur becomes sulphuric acid, and the iron becomes prot- 
oxide of iron. The two combined, then, form sulphate of 
8* 



90 MANGANESE — ZINC. 

iron (copperas). Copperas is prepared on a large scale by 
exposing certain slaty rocks, abounding in pyrites, to tbe 
action of the air. The sulphuret of iron being converted, 
as we have just seen, into the sulphate, the impure mass is 
treated with water, which dissolves out the newly formed 
salt. When most of the water has been driven off by eva- 
poration, the copperas is deposited in a crystalline mass, as 
the concentrated solution becomes cool. 

MANGANESE (Sj/mhol, Mn ; At. Wf. 27.6). 

120. This is a hard and very infusible metal, resembling 
iron in many of its chemical properties. It forms numci'ous 
compounds with oxygen ; but the only one of sufficient inte- 
rest to demand our attention now, is the jJcroxiVZe, or hIacJc 
oxide (Mn02). The principal use to which it is applied, is 
in the separation of chlorine from muriatic acid (§ 78). 
From its being employed in glass factories to remove the 
green color from glass, it has received the name of " glass- 
maker's soap." 

ZINC {Sijmbol, Zn; At. TTl 33). 

121. We have learned something of the properties of zinc 
from its use in preparing hydrogen (§ 59). When polished, 
it is a bright metal of a blueish white color. It is brittle 
when cold ; but when heated to 250°, it may be rolled into 
thin sheets. Zinc is combustible. Exj:). Place a few frag- 
ments of the metal in an iron spoon, and cover them with a 
little plate of iron. Put the spoon into the fire till it be- 
comes red-hot; then remove the cover quickly, and the zinc 
will take fire. A white, flocculent substance will be formed, 
which is protoxide of zinc. 

Zinc Is used on a large scale in the manufacture of gal- 
vanic batteries. This makes it one of the most important of 
the metals. In the form of thin sheets, it is used for various 



COPPER — LEAD. 91 

purposes ; being a cheap metal, and not so liable as iron to 
be destroyed by rust. Chains, wire, and other articles, are 
frequently coated with zinc, to prevent their rusting. They 
are then said to be '' galvanized." 

COPPER (Cuj)runi) (^Si/mbol, Cu; At. Wt. 32). 

122. This is an abundant and useful metal, and is readily 
distinguished by its brownish red color. A bright surface 
of copper becomes slowly tarnished in the air, having a coat 
of red oxide formed on it. 

Blue vitriol is the sulphate of copper (CuO,S03), and 
is easily prepared by heating copper with sulphuric acid, in 
a glass or porcelain vessel. 

Experiments. — 1. Dissolve an ounce of blue vitriol in two 
ounces of boiling water, and set the solution aside in a 
saucer. As soon as it becomes cool, the saucer will be found 
to contain a quantity of beautiful blue crystals. 2. Pour off 
from the crystals the remaining solution, and add a little 
ammonia water to it; the color will be greatly deepened. 
Ammonia is a good test for the presence of copper in solu- 
tions. 

Acetate of copper is formed when copper is exposed to the 
action of vinegar and sour fruits. It is commonly called 
"verdigris," and is very poisonous, as are all the salts of 
copper. 

LEAD (Si/mlol, Pb; At. Wt. 103). 

123. The external properties of lead, and the various uses 
to which it is applied, are familiar to every one. We will 
briefly notice some of its chemical properties, and some of 
its most important compounds. 

At ordinary temperatures, a bright surface of lead is 
almost immediately tarnished by the oxygen of the air, form- 
ing over it a thin coating of oxide of lead. This prevents 



92 



TIN 



further action of the air, and preserves the metal from con- 
tinued oxidation. The oxide thus formed is called " sub- 
oxide/' and has two atoms of lead united to one of oxygen 
(PbaO). An unmelted film of this oxide is generally seen 
floating as " dross" on the surface of melted lead. If melted 
lead is exposed to a free current of air, it rapidly combines 
with oxygen, and forms PbO, which is sold under the name 
" litharge." If kept at nearly a red heat, it combines wdth 
still more oxygen, and becomes red had (Pb304, or 2PbO,- 
PbO,). 

White Imd, used so extensively in painting, is the carbo- 
nate (PbO,C02). Sugar of lead is this metal combined with 
the acid of vinegar ; it is acetate of lead. Exp. Boil a quart of 
water, and dissolve in it a half-ounce of sugar of lead. Pour 
the solution into a bottle with a wide neck, and let it stand 
until it becomes clear; then suspend in it a lump of zinc 
attached to a thread (Fig. 27), and set it on a shelf where it 
will not be disturbed; iii a day or two, the zinc will be coated 
Fig. 27. with beautiful clusters of bright crystals of lead, 
which will soon form branches extending to the 
bottom of the bottle, like an inverted tree. 
This is the " leaden tree." It shows that acetic 
acid has a stronger affinity for zinc than it has 
for lead. Acetate of lead is decomposed, and 
acetate of zinc formed. 

Galena, the most common ore of lead, is a 
sulphuret (PbS). 




TIN {Si/mhol, Sn; At. Wt. 59). 

124. Tin is a whiter metal than lead, and also much more 
fusible, melting at 442°. It is not readily tarnished by ex- 
posure to the air and moisture. Common tin icare is made 
of sheets of iron coated with tin. 



MERCURY — ANTIMONY — ARSENIC. 93 

MERCURY {St/mhol, Hg; At. Wt. 100). 

125. This is the liquid metal used in making thermometers 
and barometers. It boils at 662°, and freezes at 40° below 
zero. With oxygen, mercury forms the common and useful 
compound (HgO) called " red precipitate." Calomel is mer- 
cury combined with chlorine — tivo atoms of mercury being 
united to one of chlorine (Hg2Cl). Corrosive snhlimate, 
which is a dangerous poison, also consists of mercury and 
chlorine ; but it has only one atom of mercury united to one 
of chlorine (HgCl). If corrosive sublimate should, by any 
mistake, be taken into the stomach, the most sure and simple 
remedy is to beat up ten or twelve raw eggs, with a quart of 
water, and give the patient a tumbler full every two or three 
minutes, till he vomits. Common emetics should not be 
given. 

The beautiful red compound sold under the name of ^Ver- 
milion," is a sulphuret of mercury, HgS. 

ANTIMONY {Si/mhol, Sb; At. Wt. 129). 

126. The dark powder sold by druggists as " antimony," 
or "crude antimony," is a sulphuret (SbSj). This compound 
is sometimes given by farmers to horses and hogs, as a 
remedy for diseases of the skin. The fourth of an ounce of 
crude antimony, mixed with the same quantity of flowers of 
sulphur, and an ounce of cream of tartar, forms a good alte- 
rative medicine for a horse. 

Tartar emetic is formed by boiling oxide of antimony and 
cream of tartar together. It is the double tartrate of potassa 
and antimony. 

Antimony is of great value in the preparation of printers' 
type. The type metal is an alloy of lead and this metal. 

ARSENIC (Symbol, As ; At. Wt. 75). 
126 (a). Arsenic (or Arsenicum) is found in some rocks 
as a dark crystalline substance, which is very brittle, and 



94 SILVER — GOLD. 

volatile at a high temperature. Its presence in iron is often 
injurious by rendering the iron brittle. The only compound 
of arsenic possessing much practical interest, is arsenious 
acid (AsOg), which is sold under the names "arsenic," 
" rats'-bane," etc. It is a terrible poison, and should be so 
kept that it may not be liable to improper use by vicious 
persons, and that it may not be used by mistake for other 
substances of similar appearance. 

For a more full description of this substance and its com- 
pounds, the reader is referred to works on chemistry. 

The best antidotes for arsenic are : (1) A powerful emetic; 
and (2) A free dose of hydrated oxide of iron (§ 117), or 
calcined magnesia. White of eggs, beaten and stirred into 
milk, should then be given promptly and freely. 

SILVER {Symbol, Ag; At. Wt. 108). 

127. This is the whitest of the metals, and, when highly 
polished, gives a beautiful and brilliant lustre. In the form 
of coins, and of various useful and ornamental articles, it is 
well known. For the preparation of such articles, the pure 
metal is not used. It is too soft to be used alone. About 
ten per cent, of copper is added, to give it proper hardness 
and durability. 

Silver dissolves readily in nitric acid, forming " lunar 
caustic," which is nitrate of silver. The sulphur of sul- 
phuretted hydrogen, or of any soluble sulphuret, combines 
readily with silver, and gives it a dark surface. 

GOLD (Symhol, Au; At F?. 98). 

128. Gold is the most beautiful of the metals, owing to its 
fine color and lustre ; but, like silver, it is too soft to be used 
in its pure form. The standard gold of coins contains tea 
per cent, of copper. 



ALLOYS QUESTIONS. 95 

ALLOYS. 

129. An alloy is a compound formed by the union of two 
or more metals, in any proportions whatever. 

Gold and sdver coins have been mentioned as alloys of 90 
parts of gold or silver, with 10 of copper. 

T;yp€ metal is composed of 3 parts of lead, and 1 part of 
antimony. 

Brass contains about 1 part of zinc to 2 parts of copper. 
Pinchheck is also an alloy of copper and zinc. 

Bell metal, hronze, and gun metal, are alloys of copper 
with different quantities of tin. 

German silver has no real silver in it, but is a compound 
of copper, zinc, and nickel, in the proportion of 10 parts of 
copper to 6 of zinc, and 4 of nickel. The nickel gives 
whiteness to the compound, and also makes it malleable. 

Britannia is an alloy of 100 parts of tin, fused with 10 
parts of antimony, and 2 of copper. Sometimes, instead of 
10 parts of antimony, 8 of antimony and 2 of bismuth are 
used. 

Soft solder is formed by fusing tin and lead together. 
Pine solder has 2 parts of tin, and 1 of lead; coarse solder, 
1 part of tin and 2 of lead. 



QUESTIONS ON CHAPTER V. 

1 86. IIow many metals are known? Are they all important? 
What are ores? Native metals? What do metals form with oxy- 
gen? What are FeO, FejOg, and FeOj? AVhat are sulphurets? 
Mention some, and give their symbols. What are salts of the metals? 
Mention some. 

87. What are alkalies ? What is the " volatile alkali " ? 

88. Symbol and atomic weight of Potassium? Its properties? 
Experiment? Product of the combination? 

89. Where is carbonate of potassa abundant ? How procured ? 
What is common lye ? 

90. 91, 92. IIow can you form nitre? Explain the experiment. 



96 QUESTIONS. 

Foi- •what is this substance used? What is said of sulphate of 
potiissa ? For what is the chlorate used ? 

93. Symbol and atomic weight of Sodium? Properties? "What is 
the base of soda salts ? 

94, 95. For what is chloride of sodium used ? Whence obtained ? 
How is sulphate of soda prepared ? What acid is liberated at the 
same time? Of what use is sulphate of soda in agriculture? 

96, 97, 98. Preparation of carbonate of soda ? Of the bicarbon- 
ate? Use of the bicarbonate? How does it make bread light? 
Where is nitrate of soda found? What is said of soda salts when 
they abound in a soil ? 

99, 100. Symbol and atomic weight of Calcium? Its most im- 
portant compounds ? What is lime ? How prepared ? Explain 
the process of slacking lime? What change takes place in the 
lime? How is the weight affected? What is air-slacked lime? 
How is it shown to be a carbonate? What influence has lime on a 
salt of ammonia? How illustrated? ES'ect of lime mixed with 
organic manures? 

101. AVhat is mortar? Explain its consolidation. 

102. What are common forms of carbonate of lime? How dis- 
tinguished from other salts of lime ? When does water dissolve 
carbonate of lime ? Explain the formation of stalactites. 

103. Of what is gypsum composed ? What names are given to it 
under its several forms? Explain the first experiment with gypsum ; 
the second. Of what use in agriculture ? 

104. 105. In what condition is phosphate of lime found? How 
obtained from bones ? What is said of nitrate of lime ? How formed 
in the soil? What is said of silicate of lime? 

106. What does oxide of barium resemble? For what is the 
chlorate used? Illustrate. What salt of barium has been used in 
agriculture ? 

107, 108. Sjanbol and atomic weight of 3Iagnesium? What is 
magnesia? How is calcined magnesia formed? Composition of 
Epsom salts? — of talc? Is magnesia found in plants? Is it im- 
portant in plants ? Is it ever injurious ? 

109, 110, 111. Symbol and atomic weight of Aluminum? Is this 
a useful metal ? Composition of alumina? In what minerals is it 
found ? Composition of clay ? Purest forms of clay ? Absorbent 
power of clay? Are stiff' clay soils easily managed? 



QUESTIONS. 07 

112, 113. How is clay combined in many rocks? How are such 
rocks decomposed ? AVliat is alum ? Burnt alum ? 

114. Symbol and atomic weight oi Iron? Its importance? Its 
abundance ? Stockhardt's remarks about iron ? 

115. Forms of iron used in the arts? What is cast-iron? How 
is fusibility of iron increased? How is malleable cast-iron pre- 
pared? Bar-iron? Sheet-iron? Wire? Steel? Cast-steel? 

116. What is iron-rust ? How may iron be burnt ? Experiment. 

117. Base of most of the salts of iron? Influence of air upon 
it? Sediment of chalybeate springs? Coloring matter of rocks 
and soils ? Magnetic oxide ? Load-stone ? 

118. 119. What of carbonate of iron? Of sulphate? Its uses? 
Sulphuret of iron? Bisulphuret? Its uses? 

120. Symbol and atomic weight of Manganese? What oxide is 
here mentioned ? Its uses? 

121. Symbol and atomic weight of Zinc? For what have we used 
Zn? Properties? Experiment? For what used on a large scale? 
Galvanized iron ? 

122. Symbol and atomic weight of Cojojoer .? Properties? What 
is blue vitriol ? Explain the experiments. "Verdigris"? 

123. Symbol and atomic weight of ieatf.? External properties? 
How tarnished? Dross of lead? How is "litharge" prepared? 
Its composition ? "Red lead"? "White lead"? " Sugar of lead" ? 
Describe the leaden tree. Galena ? 

124. 125. Describe Tin. What is "sheet-tin"? What is there 
peculiar a.ho\ii Blercury? For what used? What is "calomel"? 
" Corrosive sublimate " ? Antidote ? "Vermilion " ? 

126. What is " crude antimony"? Uses? Tartar emetic ? Type- 
metal ? Describe Arseniaim. What is white arsenic ? Antidotes ? 

127, 128. Describe Silver. Its uses? Why alloyed? "Lunar 
caustic"? What of Gold? 

129. What is an alloy ? Type-metal? Brass? Bell-metal, bronze, 
and gun-metal ? German-silver? Britannia? Solders? 



ORGANIC CHEMISTRY. 



CHAPTER VI. 

ORGANIC CHEMISTRY. 

130. If we examine closely a piece of wood, or a part of 
any plant, we find it consisting of fine fibres, and little tubes 
or cells of a peculiar form. Any part of an animal, when 
examined in the same way, is found to have a structure pe- 
culiar to itself. The plant has its roots, its leaves, its fibres, 
its sap-vessels ; the animal its stomach, its lungs, its muscles, 
its veins, etc. These are organs; hence the matter of which 
the diiferent parts of plants and animals are composed, is 
called '' organic matter." 

131. The greater part of all organic matter is composed 
of four simple elements ; namely, carhon, hydrogen, oxygen, 
and nitrogen. These are, hence, often spoken of as " tlie 
organic elements." Sometimes they are all found in the 
same substance, as in a piece of cheese. At other times we 
find only three of them associated together, as in sugar, 
which is composed of carbon, hydrogen, and oxygen. Then 
again, only two may be found together, as in the oil of tur- 
pentine, where we find only carbon and hydrogen. 

Snlphtir and 2}^tos2)horus frequently enter into the compo- 
sition of organic bodies, in small quantities. The white of 
the egg contains some sulphur. The brains of animals con- 
tain phosphorus. 

132. Mineral Part of Plants and Animals. — When we 
burn any portion of vegetable or animal matter, we always 
find something left, which we call " ashes." The organic 
elements, carbon, hydrogen, oxygen, and nitrogen, form 



ORGANIC CHE INI 1ST RT. 



99 



volatile compounds with each other, or with the oxygen of 
the air, during combustion, and disappear j but the ashes, 
being involatile, remain, forming what is known as the 
"inorganic part" of the burnt substance. 

In ashes we find a variety of substances. The bases, 
potassa, soda, lime, magnesia, oxide of iron, and oxide of 
manganese ; with the acidis, phosphoric, sulphuric, and silicic; 
also chlorine and fluorine, are found in the ashes of plants, 
and most of them also in the ashes of animal bodies. 

133. Proximate Constituents. — The four principal 
organic elements of plants and animals (§ 131) unite in a 
great variety of forms, giving rise to compounds which exist 
together in the same body, but are distinct from one another, 
and may generally be separated without change. The com- 
pounds, then, which, united, form any part of a plant or 
animal, are its " proximate constituents." 

Illustration. — Take a little lump of flour-dough, and knead 
it on a fine sieve, or piece of muslin tied over the mouth of 
a bowl, while some one pours a 
small stream of water upon it 
(Fig. 28). Continue the ope- 
ration till the water passing 
through the sieve ceases to have 
a milky appearance. There will 
be a cohesive mass still left on 
the sieve : this is the gluten of 
wheat. Letthe water with which 
the dough was washed, stand a 
few hours, till it becomes clear : 
the white powder which settles 
in the bottom is starch. Gluten and starch are two of the 
"proximate constituents" of wheat. 

We will now study the composition and properties of the 
proximate and mineral constituents of plants and animals, 



Fig. 28. 




100 VEGETABLE CHEMISTRY. 

separately, under the heads of " Vegetable Chemistry " and 
"Animal Chemistry." 

VEGETABLE CHEMISTRY. 

134. Groups. — Many of the proximate elements found 
in different plants, or in different parts of the same plant, 
are very similar in composition, and may frequently be trans- 
formed into one another. When we find a number of such 
compounds, we may place them together in one gi-onp. 

135. Starch Group. — There are a number of substances, 
composed of carbon, united with hydrogen and oxygen in 
the proportion in which they form water. Among these, 
starch is conspicuous ; and hence they constitute the " starch 
group." We shall notice a few of the most important. 
These are : 1. VegetaUe fibre or cellulose ^ 2. Gum; 3. Starch; 
4. Sugar; 5. Pectose. 

136. Vegetahle fibre is found almost perfectly pure in the 
fibre of cotton, and in clean white linen. It forms the solid, 
insoluble part of wood, and of the stalks of plants. In the 
stalks and leaves of green vegetable substances, it is soft, 
and, to some extent, digestible by animals. In dry straw, it 
is harder and less digestible. It forms the outer coating of 
grain — the bran. In the outer part of peach and plum 
stones, and in the shells of nuts, it is very firm and hard. 
The formula, representing a compound atom of cellulose, is 
C24H2o02o- If we multiply the atomic weights of the carbon, 
hydrogen, and oxygen, by the number of atoms of each found 
in this compound atom, we find them in the proportion of 
144 parts of C, 20 of H, and 160 of 0. 

The great importance of vegetable fibre is evident, when 
we reflect for a moment upon the various purposes it serves. 
It is the frame-work of the vegetable kingdom; it is the 
chief component of fuel ; cotton and linen goods are made 
of it, in its purest natural form ; it is the principal constituent 
of all varieties of paper. 



SUGARS, 



101 



Pig. 29. 



137. S'arch (C2,ILo02o). — Starch lias the same propor- 
tions of its elements as vegetable fibre, but these elements 
seem to be combined in somewhat diflferent form, so as to 
give different properties to the two substances. 

The cultivated grains are the most abundant source of 
starch. It is also obtained abundantly from the potato. It 
exists in greater or less quantities in numerous plants, espe- 
cially in their green state. 

To the naked eye, starch appears to be a very fine white 
powder, but when examined with a microscope it is found to 
consist of little granules, having an 
oi'ganized structure. Fig. 29 repre- 
sents the form of starch grains as 
they exist in the potato. 

Experiment. — Cold water will not 
produce any change on starch, but 
when the granules are first mixed up 
with a little cold water, and then 
poured into a much larger quantity of boiling water, they at 
once burst, and form an almost transparent solution, called 
'< starch water." If dry starch is heated to 300° or 400°, it 
becomes soluble in cold water. In this form it is sold as 
■" British gum." 

138. Starch water is rendered more perfectly fluid and 
transparent by being moderately heated with a little dilute 
sulphuric acid, or with an infusion of malt. The starch 
undergoes a slight change, and becomes what is called 
"dextrine." If the solution of dextrine with sulphuric acid 
is boiled for several hours, the dextrine is converted into 
grape-sugar. 

S UGARS. 

139. a. Grape-sugar, Q2ji2S^u-\-^ (J^O'). — This variety 
of sugar is found in many ripe fruits, but especially in the 
sweet kinds of grape ; hence its name. Raisins are dried 

9* 




102 SUGARS. 

grapes, and the white sweet grains found amongst them are 
particles of this sugar. Starch will yield more than its own 
weight of grape-sugar by the process mentioned in § 138. 
By a somewhat similar process it may also be prepared from 
linen or cotton rags ! — (See Foivnes Chcmistrij, p. 335.) 

" Many unripe fruits, as the apple, contain a large quan- 
tity of starch, but no sugar. After the fruit is fully grown, 
the starch gradually disappears, and we find in its place 
grape-sugar. This change constitutes the ripening of fruits, 
and, as is well known, will take place after they are gath- 
ered." — SilUnian. 

140. h. Cane-sxigar (C24H22O22) is obtained in immense 
quantities from sugar-cane, sugar-maple, and beets. It is 
also found in green corn-stalks, grass, and a variety of other 
substances. It is much sweeter and more soluble than 
grape-sugar. 

141. c. Sugar of Milk {Lactose) C24H20O20 + 4 (HO) 

This is a variety of sugar found in milk. After the curd 
of milk is taken out, as in making cheese, the whey holds 
this sugar in solution. By boiling either cane-sugar, or lac- 
tose, with dilute sulphuric acid, grape-sugar is formed. 

142. Gum (C24H20O20) has the same composition as starch, 
and vegetable fibre. One of its purest forms is seen in gum 
Arabic. It also exudes from the peach and cherry trees. 
In the seeds of many plants it is abundant. The mucilage 
of flaxseed is a form of gum. There is also a portion of it 
in all of our cultivated grains, and in almost all plants. 
Boiled in dilute sulphuric acid it becomes grape-sugar. 

143. Pectose, or Pectine, is closely allied to gum. It is 
the substance which gives to the juices of many fruits the 
property of forming jellies. In such roots as the turnip and 
parsnip, pectine takes the place which starch occupies in the 
potato. As an article of food, it serves the same purpose as 
starch. 



PRODUCTS OF THE STARCH GROUP. 103 

144. All the substances liere described as having a com- 
position similar to vegetable fibre, may be converted into 
that substance during the growth of plants, under the influ- 
ence of that mysterious principle which we call "vitality." 

NATURAL PRODUCTS OF THE STARCH GROUP. 

145. Peat is the product of decaying vegetable fibre 
under water. In bogs, large quantities of vegetable matter 
are often accumulated. Then, difi"erent mosses grow upon 
the surface of the water, die, and sink to the bottom, there 
to undergo the process of decay. During the decay of such 
masses of vegetable matter, carbonic acid escapes, with some 
carburetted hydrogen (C2H4). The residue is chiefly carbon, 
a part of which is combined with a little remaining hydrogen 
and oxygen, forming a sort of bituminous substance. Long- 
continued pressure, and a little further advance in the decom- 
position of peat, would convert it into bituminous coal. 

146. Peat bogs are found generally in latitudes north of 
37°. In some countries, peat is used for fuel. It is also 
regarded as a valuable source of gas for lighting houses and 
cities. For agricultural purposes, it is valuable, especially 
as an absorbent of ammonia, when mingled with stable and 
barnyard manures. 

147. Humus is another valuable product of the decay of 
vegetable fibre. The vegetable mould, which is produced so 
abundantly in forests, by the decay of leaves and twigs of 
trees is humus. So, the dark coloring matter of soils, abound- 
ing in organic substances, is humus. Its formation requires 
the presence of air and moisture. A mass of moist straw, 
leaves, or hay, lying upon the surface of the ground, so that 
the air can have access to it, soon begins to 7-ot, as we say. 
The change produced on the vegetable fibre is somewhat 
different from that which results in the formation of peat. 
It resembles a slow combustion. The oxygen of the air com- 



104 PRODUCTS OF THE STARCH GROUP. 

bines with a part of the carbon, converting it into carbonic 
gas v.hich escapes into the air; but the hydrogen and oxygen 
of the vegetable fibre disappear much more rapidly than the 
carbon, and the large excess of carbon thus accumulated 
gives the dark brown color to the vegetable mould or humus. 
Humus is different in composition at different stages of its 
formation. It contains several distinct substances, some of 
which are acids. Of these, humic and ulmic acids may be 
mentioned as important. They have a strong affinity for 
ammonia, and combine also with other bases, forming soluble 
salts. In this condition, they are supposed to enter the 
roots of plants, and afford them nourishment. 

Experiment. — Dissolve an ounce of carbonate of soda in a 
quart of water ; then add two or three ounces of well de- 
cayed mould, and boil the mixture a few minutes. A brown 
solution of soda, combined with the humic and other acids 
of the mould, will be formed. If muriatic acid is now added 
till the solution becomes sour, the soda will be taken up by 
the muriatic acid, and the vegetable acids (humic, ulmic, 
etc.), being set free, soon fall to the bottom as a brown inso- 
luble precipitate. 

The value of humus in soils, and in the preservation of 
manures, will be mentioned under the composition of soils, 
and management of manures. 

148. Alcohol (C4II6O2). — This is one of the important 
products of the starch group. It is generally produced from 
grape sugar, by a process which we call the " vinous fermen- 
tation." It consists in breaking up an atom of grape sugar 
into four atoms of alcohol, and eight atoms of carbonic acid. 
An atom of the sugar, C24H24O24 = 8 (CO,) + 4 (C^ITeO^). 

A solution of pure sugar will not undergo this change, 
even in the open air ; but if a little yeast, or white of e^g, 
be stirred into the solution, and the temperature be kept up 
to about 75° or 80°, little bubbles of gas will soon begin 



PRODUCTS OF THE STARCH GROUP. 105 

to rise rapidly, and the odor of alcohol will become per- 
ceptible. 

It has already been stated that starch and cane sugar are 
readily changed to grape sugar by an infusion of malt. 
Yeast produces the same effect. This change is always sui>- 
posed to take place before starch and cane sugar can be con- 
verted into alcohol. 

149. Alcohol is separated from the water, and other sub- 
stances with which it is mixed, by distillation (§ 23) ; but 
during the first distillation, a large quantity of water passes 
over with it, giving but a weak solution. By repeated dis- 
tillations, the temperature being reduced each time, the 
alcohol may be obtained so nearly pure as to contain only 
about 15 per cent, of water. This is " commercial alcohol." 
If absolutely pure alcohol is required, the common alcohol 
must be mixed with unslacked lime, or fused chloride of cal- 
cium, either of which will combine with the water, and not 
with the alcohol. The latter may then be distilled from the 
mixture in a pure form. 

Alcohol burns with a pale blue flame, without smoke, pro- 
ducing a high degree of heat. This makes it valuable to be 
used in lamps for heating purposes. 

The alcohol of wines is produced by the fermentation of 
the sugar of the grapes. So alcohol is generated in cider, 
and in the juices of many fruits containing sugar. 

150. " Raisirtff Bread." — Flour contains some sngar. 
When yeast is added to a mass of dough, and the mixture 
set aside for several hours in a warm place, fermentation 
takes place throughout the mass ; alcohol and carbonic gas 
are generated. The bubbles of gas set free make the dough 
porous, and cause it to '' rise." During the baking, the heat 
expands the little gas bubbles, and this causes an increased 
l-ising. The vapor of alcohol generated within the dough 



106 TRODUCTS OF THE STARCH GROUP. 

may aid in producing this result, but the alcohol is expelled 
by the heut before the baking is completed. 

151. Acetic Acid (vinegar acid). — This is the most im- 
portant product of alcohol. It is produced by removing a 
part of the hydrogen from alcohol, and adding more oxygen. 
Pure alcohol, or alcohol diluted with pure water, will not 
undergo this change by exposure to the air ; but if a little 
yeast, or mother of vinegar, or some similar compound, be 
added to a solution of alcohol, the change to acetic acid soon 
begins. Thus alcohol is C4H6O2 ; if two atoms of its hydro- 
gen are removed, it becomes C4H4O2, which is called " alde- 
hyde." If two more atoms of oxygen combine with the 
aldehyde, it takes the form C4H303,HO,* which is acetic 
acid in its most concentrated form. 

152. Vinegar. — The juices of fruits, such as cider and 
wines, contain enough of albuminous matter to cause their 
sugar to be changed first into alcohol ; and then, if air be 
freely admitted, acetic acid begins at once to be produced 
from this alcohol. If there is any dextrine (soluble starch) 
in the liquid, it will also produce, first sugar, then alcohol, 
then acetic acid. The strength of the vinegar formed from 
wine or cider, or from a solution of sugar or molasses, will 
depend upon the quantity of fermentable matter (sugar and 
dextrine) present, and the completeness of the fermentation. 
Free access of air is necessary to produce acetic acid, because 
the air is the agency by which part of the hydrogen is re- 
moved from alcohol, and an additional quantity of oxygen 
supplied. The very rapid fermentation of vinegar is some- 
times caused by passing it over a mass of beech or sugar- 
maple shavings placed in a large barrel, with holes near the 
bottom for allowing a free circulation of air. When vinegar 
is fermented in a half-filled cask (the common way), it should 
be frequently agitated, so as to cause the air to mingle with it. 

* Sometimes written C^H^O^ (see Silliman). 



PROTEIN E GROUP. 107 

Acetates. — Acetic acid combines Tvitli bases such as 
potassa, soda, lime, etc., forming a class of salts called " ace- 
tates." Acetate of potassa (KO,C4H303) is easily formed 
by dissolving carbonate of potassa in vinegar until efferves- 
cence ceases. The vinegar loses its sour taste, being now a 
solution of acetate of potassa. A solution of acetate of soda 
may be prepared in the same way. Acetate of alumina is 
extensively used in dyeing, for the purpose of fixing the 
colors. Sugar of lead is the acetate of lead, with 3 atoms 
of water of crystallization (PbO,C4H303 + 3H0). Verdi- 
gris is acetate of copper. This, as well as acetate of lead, is 
very poisonous. When liquids containing acetic acid are 
heated, or kept for some time in copper or brass vessels, ace- 
tate of copper is formed to soijie extent. 

153. Lactic Acid. — When sugar in solution is mixed 
with a little curd of milk, a peculiar kind of fermentation 
takes place, by which the sugar is converted into an acid 
different from acetic acid. The same acid is formed from 
lactose during the spontaneous souring of milk. From the 
fact of its being the natural acid of sour milk, it is called 
" lactic acid." 

PROTEINE GROUP. 

154. We find in plants associated with the starch group, 
another very important class of compounds, which are known 
as jJi'oteine bodies. Besides carbon, hydrogen, and oxygen, 
they all contain nitrogen; hence the term '' nitrogenized" is 
often applied to them. They also contain small portions of 
sulphur and phosphorus. The most important of them are 
gluten, vegetable albumen, and vegetable caseine. They all 
resemble the white of eggs in composition. 

155. Gluten. — When the starch is washed out of a piece 
of dough, by the experiment in § 133, the adhesive mass 
which remains is gluten. It has nearly the same composition 



108 r R O T E I N E G R O U P . 

as the fibrous part of lean meat, and is hence called "vege- 
table fibrin." It is insoluble in water. 

156. Vegetable Albumen. — If the water used in wash- 
ing the starch out of dough be allowed to stand till it be- 
comes perfectly clear, and is then poured off and boiled, it 
becomes turbid. It had removed from the flour a form of 
proteine matter, which was soluble until heated to a tempe- 
rature above 160° ; above that temperature it becomes inso- 
luble (coagulates), like the white of an egg dissolved in 
water, and heated to the same temperature. It is called 
"vegetable albumen," because of its similarity to the white 
(albumen) of the egg. 

157. Vegetable Caseine. — This is a form of proteine 
matter found most abundantly in peas and beans. Exp. 
Crush some beans or peas in a mortar, or in any other way, 
to the condition of coarse meal, and soak them in water for 
several hours; then add a little vinegar to the clear solution. 
A white substance is set free and deposited, which, from its 
likeness to the caseine or curd of milk, has received the 
name we have applied to it. It is also called •" legumen." 

158. These proteine compounds are of the highest im- 
portance in all vegetable substances used as food for animals. 
We shall hereafter learn that the greater part of the animal 
body is composed of proteine substances, similar to those we 
have found in vegetables. As all animals derive their nou- 
rishment either directly or indirectly from vegetable food, 
this food must possess a nutritive value somewhat propor- 
tional to the quantity of proteine matter it contains. 

159. Our ordinary crops all contain some form of proteine, 
but the quantity is fovmd to vary considerably even in the 
same kind of plant. The grains, such as wheat, Indian corn, 
etc., contain from 8 to 20 per cent. Hay contains from 2 
to 8 per cent. It is found also in the sap of ti'ees, and in 
various fruits. 



VEGETABLE OILS. i09 

If proteine compounds are dried, they may be preserved 
for any length of time in that condition ; but when exposed 
to the united action of air and moisture, they very soon un- 
dergo decomposition — they become putrid. The result of 
their decomposition is the production of carbonic gas, water, 
and ammonia. The sulphur and phosphorus escape in com- 
bination with hydrogen, producing two gases of very dis- 
agreeable odor (sulphuretted and phosphuretted hydrogen). 

160. The presence of proteine compounds causes rapid 
changes in other bodies with which they are in contact. 
The abundal^^ of albumen in the sap of trees causes the 
pap-wood to decay more rapidly than other parts of the tree. 
Animal matter, being made up largely of proteine substances, 
becomes putrid very soon after life is extinct. 

VEGETABLE OILS. 

161. Oily matter of some kind is found in almost every 
variety of plant. It is found in the stalks, leaves, flowers, 
and seeds. Some vegetable oils are volatile; some on expo- 
sure to the air form a solid, dry film over the surface of any 
body upon which they are spread — these are "drying oils." 
Others are not readily changed by exposure to the air — 
these are " fixed oils." 

162. Volatile or Essential Oils. — These are called 
''essential" oils, because, when dissolved in alcohol, they 
form " essences." We can notice only a few of the most 
important. 

163. Oil op Turpentine {Camphene') is prepared by 
distilling the crude turpentine which exudes from pine- 
trees. It is distilled with water (§ 23) ; and as the oil and 
water become condensed in the receiver, they at once se|>a- 
rate, the oil floating on the surfiice. After the first distilla- 
tion, it is called " spirits of turpentine," and still contains 
some resinous matter. To free it from this, it is distilled 

10 



no VEGETABLE OILS. 

again, and is then called "camphene." Its composition is 
represented by the formula : C5H4 (or, C,oHs). 

Camphene is a clear liquid, volatile and combustible. It 
burns with the production of a large quantity of smoke. 
The smoke consists of unburnt carbon. The hydrogen of 
the oil is more combustible than the carbon, and combines 
first with the oxygen of the surrounding air : the supply of 
oxygen not being sufiicient for both, the carbon is set free 
as smoke. There are lamps constructed so as to throw a 
strong current of air against the sides of the flame, and in 
this way oxygen enough is supplied to make the combustion 
complete. 

164. Uses. — Oil of turpentine is extensively used as a 
solvent for varnishes, and in the preparation of paints; also 
for dissolving india-rubber and gutta-percha. But for no 
purpose is it so largely used as for producing light. It is 
frequently burnt alone in lamps constructed for the purpose 
(§163), but most largely consumed in the form of 

Burning Fluid. — We have already learned, that cam- 
phene alone has too much carbon in it to adapt it well for 
burning. Alcohol, on the other hand, has too little carbon 
in it to produce much light. The brightness of flame is 
caused by atoms of carbon suspended in it, and kept at a 
white or yellow heat until they reach the outer part of the 
flame, where they meet with the oxygen of the air, and are 
entirely consumed. If there is a deficiency of carbon, it is 
consumed too quickly to give much light, as in alcohol ; if 
an excess of carbon, smoke is the result, as in camphene 
alone. Now, when a portion of camphene is dissolved in 
alcohol, it supplies the deficiency of carbon ; and in this 
way the two liquids counteract the defects of each other. 
Such a solution is common " burning fluid." 

Oils of orange, lemon, citron, hergamot, peppei-, etc. are 
similar in composition, and in some of their properties^ to 



KESINS. Ill 

oil of turpentine. Camphor is also a volatile oil, obtained 
from a tree (laurus ca'^npliord). 

Drying Oils are obtained cbiefly from the seeds of 
plants. Among the most common and useful are linseed 
oil (from tbe seed of flax), hemjiseed oil, walnut oil, castor 
oil (used also in medicine and perfumery), and oil of cotton- 
seeds, whicli seems to have some drying properties, and is 
hence sometimes classed with drying oils. These oils are 
used for mixing paints ; and by the action of the air they 
are converted into a firm resinous substance, which adheres 
to the surface painted, and retains the particles of coloring 
matter, which were not dissolved in it, but simply mixed 
with it. 

166. Fixed Vegetable Oils are such as retain their 
oily character when exposed to the air. They often absorb 
oxygen when exposed to the air for some time, and produce 
acids of strong odor : they become rancid. 

Olive Oil is one of the most common and useful of the 
fixed vegetable oils. It is obtained from the pulp of the 
olive fruit. It is used for food, for oiling machinery, and 
for various other purposes. Palm oil, from the fruit of the 
palm-tree, is solid at common temperatures. It is used ex- 
tensively for making soap. Almond oil, obtained from the 
sweet almond, is highly valuable in the manufacture of soap, 
and in the preparation of some ointments. 

167. Oil is one of the necessary articles of food for ani- 
mals; and, in order to meet this necessity, the kind hand 
of Providence has made the crops produced by the earthy an 
abundant source of this, as well as the other elements of 
nutrition demanded by the animal kingdom. 

resins. 

168. Some of the vegetable oils become oxidized by ex- 
posure to the air, and form solid bodies called "resins." 



112 RESINS. 

Of these, yve find the one most common nncl most important, 
formed by the oxidation of oil of turpentine. As the crude 
turpentine collects in the wounds cut in the sides of trees 
for the purpose, it gradually absorbs oxygen, and becomes 
partially converted into resin. By distillation the oil of 
turpentine is removed, and an involatile resinous mass re- 
mains. This generally passes under the name of "rosin." 

169. Uses of Rosin. — (1) It is frequently employed in 
the preparation of illuminating gases. (2) Mixed with ani- 
mal fats, it is used in the manufacture of " rosin soap." (3) 
A soap prepared from rosin is used for giving compactness 
and smooth surface to paper. It is mingled with the mate- 
rial in making the paper. (^Porter?) 

Copal, Lac, and Mastic are some of the resins commonly 
employed as varnishes. Lac dissolves most readily in alco- 
hol. Besides its use in varnishing, it is largely consumed in 
making sealing-ioax, which consists of lac (shellac) mixed 
with a little Venice turpentine, and some coloring matter. 

170. Gum Resins are the products of plants in warm 
climates. They contain both gum and resinous matter. Of 
these, india-rubber and gutta-percJia are the most important. 

171. India-rubber {CaoutcJiouc). — "This well-known 
substance is obtained by making incisions through the bark 
of certain trees of the fig or banyan species, which grow in 
S. America and the E. Indies : a milky juice flows out, 
which, upon evaporation, yields about 32 per cent of caout- 
chouc. The poppy, the lettuce, and other plants having 
viscid, milky sap, seem also to contain it. Caoutchouc, 
when pure, is white and transparent; its dark color being 
due to the blackening effect of the smoke in drying. It is 
highly elastic, and the freshly-cut surfaces adhere strongly, 
if pressed together. It is insoluble in water, alcohol, and 
acids; but dissolves in ether, naphtha, spirits of turpentine, 
and other essential oils. The solutions in ether and naphtha 



VEGETABLE ACIDS. 113 

leave the caoutchouc in an elastic state. It is a simple hydro- 
carbon, containing no oxygen, and burning with a luminous 
sooty flame. Its uses are very various. Dissolved and 
applied to fabrics, it forms water-proof cloth : it is also used 
for shoes ; and when cut into thin shreds, and boiled with 
linseed oil (4 ozs. caoutchouc to 2 lbs. of oil), it forms a 
mixture used for making boots water-tight." — Youmans. 

Vulcanized India-rubber is that which has been exposed 
to the action of melted sulphur. The sulphur, uniting with 
it, makes it more firm, and less liable to be influenced by 
changes of temperature. 

GuTTA Percha is a substance obtained, like India-rubber, 
from the sap of certain trees. It is not so elastic as India- 
rubber, and has the property of becoming so soft, when im- 
mersed for a few minutes in hot water, that it may be 
moulded to any shape with the fingers. It becomes very 
firm and hard on cooling. 

VEGETABLE ACIDS. 

172. Oxalic Acid is found in the different kinds of 
sorrel, and gives them their sour taste. It is easily pre- 
pared from sugar or starch by the action of nitric acid. 
Exjj. — Mix tlu-ec ounces of nitric acid with two ounces of 
water, and add half an ounce of sugar. Heat the mixture 
in a glass or porcelain vessel. Red vapor will soon begin to 
escape freely. Continue the heat until the solution is evapo- 
rated to one-half the original quantity, and then set it aside 
to cool. In a few hours the bottom of the vessel will be 
covered with beautiful, slender crystals of oxalic acid. Its 
composition is C203,HO. This acid is very poisonous, and 
if accidentally taken into the stomach, magnesia or lime-water 
should be given immediately. 

173. Tartaric Acid is procured chiefly from grapes. 
During the preparation of wines, a hard crust is deposited 

10* 



11-1 VEGETABLE ACIDS. 

on tlic iruicr surface of the vessels ir> v.hicli the ■wine is fer- 
mented. This crust is an acid tartrate of potassa, and v,'hcn 
purified is called " Cream of Tartar." By mingling pow- 
dered chalk with cream of tartar in water, tartrate of lime is 
formed. This is again decomposed by sulphuric acid, which 
removes the lime in an insoluble form, leaving the free tar- 
taric acid in solution ; from this it is crystallized by evapora- 
tion. The composition of this acid is C8H40,o,2HO. Tar- 
taric acid is extensively used in the preparation of efferves- 
cing powders. With carbonate of soda or potassa it causes 
rapid effervescence. 

One atom of a base is not sufficient to neutralize an atom 
of this acid. It requires two atoms of any one base, or one 
atom of two different bases. Cream of Tartar consists of 
only one atom of potassa, luiited to each atom of acid, and is 
therefore an acid salt. If an additional quantity of potassa 
or soda were added to cream of tartar in water, the acid 
would unite with a second atom of either of these bases ; or 
if the carbonates of the bases were added, the same result 
would take place, and the carbonic gas u-ould he set free. 
This is what takes place when cream of tartar and carbonate 
of soda are mingled together in making bread. 

174. Citric Acid is found abundantly in lemon juice, 
and in the orange. 3Ialic acid is the acid of apples, goose- 
berries, and many other fruits. It is also the acid oi garden 
rlinharl). 

175. Tannic Acid is the astringent substance in oak 
bark, and in the leaves and bark of many trees. It is found 
in tea, to which it gives an astringent taste. When the 
skins of animals are steeped for some time in an infusion of 
oak or hemlock bark, the tannic acid combines with the skin 

' and forms leather (see § 589). 

Inh is a compound of iron and tannic acid, or rather of 
peroxide of iron and this acid. For making ink, the tannic 



VEGETABLE BASES. 115 

acid is obtained from nut-galls (a kind of excrescence found 
on tlie leaves of some species of oak). 

VEGETABLE BASES. 

176. Plants often produce bases, as well as acids. These 
are not free, as they exist in the plant, but generally in com- 
bination with acids. They possess the property of neutral- 
izing acids, and are hence called '' vegetable alkaloids." 
They all contain nitrogen, and ai-e in some respects similar 
to ammonia. Many of them are valuable for their medicinal 
properties. We can notice only a few of the most important. 

177. Quinine is obtained from Peruvian harh. It is this 
alkaloid, together with another called " cinchonine," which 
gives Peruvian bark its medicinal value. 

Ilorphine and Narcothie are the alkaloids of opium, and 
give that drug its peculiar properties. Strychnine is found 
in the nux-vomica, St. Ignatius's bean, and some other sub- 
stances. It is a most fatal poison. Theine, or caffeine, is a 
substance found in both tea and coflPee, having stimulating 
properties, which give these articles their value as beverages. 
Nicotine is a very poisonous alkaloid existing in tobacco. 
Taken in small quantities into the stomach, as it is by 
tobacco-chewers, or into the lungs, as it is by smokers, it 
produces a kind of mild intoxication, and on this account is 
esteemed a great luxury. 

COLORING COMPOUNDS (dye-stuffs'). 

178. Indigo. — This common blue substance is obtained 
from plants. It is colorless in the juice of the plant, but 
when exposed to the air it becomes blue. Its use in dyeing 
is well known. 

Madder is the root of a plant cultivated in different parts 
of the world. The root i« dried and ground to a powder, 



116 COLORING COMPOUNDS. 

from wliich the coloring matter is extracted for dyeing 
purposes. 

Logwood is found as a common tree in Central America, 
and is sold either in the form of wood, or an extract from the 
wood, and used as a coloring substance. 

179. Colors of Flowers, Leaves, &c. — The beautiful 
colors of flowers are caused by some transient compounds, 
seldom permanent enough to be separated, or even to survive 
the drying of the bodies in which they exist. 

Chlorophyll is the name given to the green coloring 
matter of leaves, and other green parts of plants. It " is 
one of the most widely diffused substances in the vegetable 
kingdom, since it occurs in all parts of the plant which pos- 
sess a green color. As found in plants, it is a mixture of 
wax and of several coloring matters not well known. It 
need hardly be said that it is not soluble in water ; for if it 
were, the water would become green on flowing over meadows. 
The expressed juice's of the herbs are indeed green, but it is 
obvious from their turbidness that the leaf-green is only 
mechanically mixed with the liquid. We become still more 
fully convinced of this by the separation of the coloring 
matter which takes place when the juices are boiled, or 
allowed to remain for some time in repose. If, on the other 
hand, alcohol, ether, or weak lye, is poured on the green 
leaves, we obtain green solutions ; hence all the tinctures of 
pharmacy which are prepared from leaves or stalks have a 
green color. The green color appears only in those parts of 
the plant which are exposed to the light ; it is obvious from 
this, that the chemical compound which we call chlorophyll 
is only generated with the cooperation of light. When sepa- 
rated from plants, this coloring matter is very soon decom- 
posed ; it is, therefore, not at all suited for a coloring sub- 
stance, except, perhaps, for cordials and other liquids. In 
the autumn it is converted in the leaves themselves, into 



QUESTIONS. 117 

leaf-yellow and leaf-red, probably by a process of oxidation." 
— Stockhardt. 

Chlorophyll contains nitrogen as well as carbon, hydrogen, 
and oxygen ; and the importance of nitrogen in fertilizers 
may give to this compound a value in green crops, of which 
we are not fully aware. 



QUESTIONS ON CHAPTER VI. 

^ 130. What do we find peculiar in a plant or an animal? What 
is organic matter? 

131. Of what elements are organic bodies chiefly composed ? What 
example is given of a substance containing all of them ? of one con- 
taining on\y three? containing oriiytwo? What two elements are 
less abundant in organic bodies ? Examples ? 

132. What is always left when an organic body is burnt? What 
elements disappear? What is the inorganic part of a body? What 
substances are found in ashes ? 

133. What is said of the compounds formed by the union of the 
organic elements ? What are proximate constituents? How illus- 
trated ? 

134. 135. When may we group substances together? What sub- 
stances constitute the starch group ? 

186. Where is pure vegetable fibre found? In what other form is 
it abundant ? What formula represents its composition ? The pro- 
portions by weight of C, H, and ? What shows the great import- 
ance of vegetable fibre ? 

137,138. Composition of /S'/'arcA ? What does it resemble in com- 
position? Most abundant sources? How does it appear under the 
microscope? Effect of cold water ? Ofhotwater? "British Gum?" 
Effect of dilute sulphuric acid on starch water ? What is the starch 
then called ? If boiled several hours with the acid, what change 
takes place ? 

139, 140, 141. Composition of (Jra/e^Si/^ar.? Where found? How 
formed from starch? Explain the ripening of fruit. Formula of 
Cane Sugar ? From what chiefly obtained ? Its qualities ? What 
is sugar of milk ? How prepared ? 

142,143,144. Composition of (?t«?! .? Examples mentioned? How 



118 QUESTIONS. 

converted into grape sugar? Vf hhi is Pectose ? What change may 
vitality produce in any member of the starch group? 

145, 14G. AVhat is Peat? Describe its formation. How converted 
into coal? Where are peat-bogs generally found? Uses of peat? 

147. What is //i/7n!;s .? In what forms does it exist? Conditions 
necessai-y to its formation? Explain the chemical changes which 
take place during its formation. Its influence on ammonia? What 
experiment is mentioned? 

148, 149, 150. Torm\x\n. 0^ Alcohol? From what produced ? Ex- 
plain the chemical changes in its formation. What is necessary to 
produce vinous fermentation in sugar ? How are starch and cane 
sugar converted into alcohol ? Explain the distillation of alcohol. 
How does it burn? Alcohol of wines? Explain the raising of bread. 
How does baking increase its liglitness ? 

151,152. What is the acid of vinegar? How produced? Explain 
its formation. How is vinegar formed ? What determines its 
strength ? Why is air necessary to its formation? Methods of pro- 
moting its fermentation? What are Acetates? Examples given? 
Uses? 

153. What is the influence of curd on a solution of sugar? Why 
called lactic acid ? 

154. What elements are contained in the proteine group ? Most 
important compounds in this group ? 

155. 156, 157. Describe Gluten. Why called vegetable fibrin? 
What is vegetable albumen ? How obtained from flour ? Why called 
albumen? From what is vegetable Caseine produced? What expe- 
riment shows its properties ? 

158, 159, 160. What of the importance of these? Why necessary 
in animal food ? Are they present in all crops ? How may they be 
preserved unchanged? Effect of air and moisture? Products of 
their decomposition ? Their influence on the decay of other bodies? 
Why do animal bodies readily decay ? 

161, 162. Where is oily matter found? What are drying oils? 
Fixed oils? Essential oils? 

163, 164. How is Oil of Turpentine formed? When called spii-its 
of turpentine? Camphene? Its formula? Describe camphene. 
Why does it smoke when burning ? How is this prevented ? Its 
uses ? What is bui-ning fluid ? What are the advantages of com- 
bining camphene and alcohol ? What other oils are similar to oil 
of tm-pentine ? 



QUESTIONS. 119 

165. From what are drying oils obtained ? Give examples. For 
■what are they used ? Explain the drying of paint. 

166, 167. What are Fixed Oils? How do they become rancid? 
What is olive oil ? Palm oil ? Almond oil ? Why are all forms of 
vegetable food provided with oil? 

168,169. yf hat are Besins ? Which is the most important ? Uses 
of rosin ? AVhat of copal, lac, etc. ? 

170, 171. Where is I?idia Rubber obtained? What other name 
has it? Its properties ? Uses? How vulcanized ? Whatofgutta 
percha ? 

172. Where is oxalic acid found? How prepared artificially? 
Give the experiment. Formula of its composition? Effect on the 
stomach ? Antidotes ? 

173, 174, 175. How is Tartaric Acid procured? Explain the col- 
lection of cream of tartar. How is tartaric acid prepared? Its 
uses ? Does one atom of a base neutralize it ? What is cream of 
tartar? Why used in bread-making? What of citric and malic 
acids? Sources of <an«2c acid ? What is leather ? Ink? 

176, 177. What of bases in plants? What are they called? With 
what do they combine? What of Quinine? Of Morphine, Narcotine, 
and Strychnine? Of Thein and Caffeine? Nicotine? 

178,179. How is /«(f!>o obtained ? Madder? Logwood? What 
of the colors of flowers, the leaves, etc. ? What is Chloi-ophyll ? 
Where found ? Is it soluble in water ? On what part of the plant 
does the green color appear? AVhat of the influence of light upon 
it ? Of what is chlorophyll composed ? 



120 MINERAL CONSTITUENTS OF PLANTS. 



CHAPTER VII. 

MINERAL CONSTITUENTS (ASHES) OF PLANTS. 

180. In § 132 the ashes of plants have been defined, and 
the substances generally found in them have been mentioned. 
The mineral constituents of the same species of plants differ 
but little, no matter where the plant may grow. The ashes 
of the oak have very nearly the same composition all over 
the world. AVheat cultivated in America differs but little, 
in the cjuantity and quality of its ashes, from that which is 
cultivated in Europe. Local causes may produce slight vari- 
ations, some of which will be hereafter noticed. 

181. Quantity of Ashes. — 1. Different parts of the same 
plant yield different quantities of ashes. For example, 100 
pounds of the dry grain of tcheat yield, when completely 
burnt, about two pounds of ashes; while 100 pounds of the 
straw yield about 6 pounds of ashes. So the grain of corn 
yields about IJ per cent, of ashes, while the stalk yields 
about 5 per cent. ; and so of other crops. 

2. Different plants yield different quantities of ashes. The 
oak, for example, gives about 2^ pounds of ashes from 100 
pounds of the wood well dried ; but hickory gives about 4 
or 5 pounds of ashes from 100 pounds of the dry wood. 

182. The relative quantity of ashes from different parts 
of the same plant, as well as from diff'ercnt kinds of plants, 
will be seen at once, by examining the following table : 



MINERAL CONSTITUENTS OF PLANTS. 121 







TABLE 


II. 








100 ft)S of dry 


Oak* yield about 2 J 


lbs 


f ashes, 


(I 


" 


Ash or Hickory 




4 or 5 


" 


(( 


<( 


(( 


Pine 




1 


<( 


(C 


<( 


(( 


Wheat Straw 




6 


(C 


ii 


« 


(< 


Stalks of Indian 














Corn 




6 


(( 


<( 


(( 


<( 


Grain of Wheat 




2 


(( 


<( 


« 


(( 


" Corn 




1^ 


(< 


« 


« 


« 


Potato (sliced and 














dried) 




4 


(( 


(( 


« 


<( 


Potato Stalks 




12 


<< 


(( 


« 


(< 


Tobacco Leaves 




20 to 23 


(( 


<i 


<< 


<( 


" Stalks 




10 to 12 


(< 


<( 


<( 


<l 


Cotton-wool 




1 


(( 


(( 


(( 


C( 


" Seeds 




4 


(( 


<( 


K 


(( 


Hay 




7 to 10 


(( 


(( 


<l 


<( 


Peas 




3 


<( 


(( 


(( 


(< 


Pea Straw 




8 


<< 


(( 



183. The quantity of ashes, in the same kind of crop, 
varies but little, as above stated, wherever that crop may be 
cultivated. A difference in soil and climate may cause slight 
difference in the quantity of ashes, but, as a general rule, 
the crops cultivated in this country give about the propor- 
tions represented in the above table, provided the crop has 
been cut in the proper state of maturity. The grain of wheat 
always gives about 2 per cent of ashes, while tobacco leaves 
seldom vary much below 20, or above 23 per cent; and so 
of other plants. 

184. Ashes from different sources vary in composition, as 
well as in quantity. 

1. The ashes from different parts of the same plant differ 
in composition. If we analyze the ashes of the grain of any 

* The bark and wood taken together. The bark alone yields 
about three times as much per cent, of ashes as the wood alone. 
11 



122 MINERAL CONSTITUENTS OV PLANTS. 

ordinary crop, as wheat, rye, or corn, and at the same time 
analyze a like quantity produced from the straw or stalks of 
the same crop, we shall find a striking difiference between 
them, in some respects. In the ashes of the grains, for in- 
stance, we find a great abundance of the 2)hosj)hates of lime, 
magnesia, and potassa j while in those from the stalks, 
we find a much smaller quantity of these phosphates, but a 
very large quantity of silica, of which there was very little 
in the grain. 

2. The ashes of different plants differ in composition. If 
we examine a hundred pounds of ashes of potatoes, we shall 
find in them about 50 lbs. o/ potassa, about 2 lbs. of lime, 
about 12 or 13 lbs. of sulphxiric acid, and about 4 lbs. of 
silica. But in the same quantity of ashes of hai/, we shall 
find only about 18 lbs. of potassa, whilst we find there about 
23 lbs. of lime, and only about 3 lbs. of sulphuric acid. 

185. The table opposite (III) gives a close approxima- 
tion to the average 6omposition of ashes from various sources. 
This table consists of the mean results of the most reliable 
analyses of ashes, made by difi'erent chemists. The author 
has made several analyses of this kind himself, and has com- 
pared them with others — taking the mean of all, as repre- 
senting what might be regarded as the nearest approxima- 
tion to a fair average composition of all the varieties here 
given. 

It will be observed that the quantity of each crop required 
to produce 100 lbs. of ashes, is given at the top of the 
column in the table assigned to that crop. We must, for 
example, burn 5000 lbs. of wheat grain, 1600 lbs. of wheat 
straw, or 450 lbs. of tobacco, in order to get 100 lbs. of the 
ashes of either of these crops ; while it would require about 
10,000 lbs. (5 tons) of potatoes, in the condition in which 
they are taken from the ground, to yield 100 lbs. of ashes. 

186. The mineral matter in plants is essential to their 



MINERAL CONSTITUENTS OF PLANTS. 123 



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124 QUESTIONS. 

growth, as we learn: 1. From its being present in the same 
plant, in about the same proportions, wherever that plant 
may grow, provided it has come to full maturity; and, 2. 
From the fact that a plant will not grow in a soil destitute 
of the mineral matter peculiar to the ashes of that plant. 

187. The mineral ingredients of plants, being involatile, 
cannot constitute any part of the atmosphere ; hence, they 
must find this part of their nourishment altogether in the soil. 
Of this part of the subject, a more full discussion will be 
given in a subsequent chapter. 



QUESTIONS ON CHAPTER VII. 

§ 180. What are the ashes of plants? What is said of their com- 
position in the same plant, wherever found ? Examples. 

181, 182, 183. What of different quantities in different jwar^s of the 
same plant? Examples. Quantities yielded by different plants? 
Examples. What does Table II. represent? Influence of soil and 
climate on the quantity of ashes? 

184, 185, 186, 187. What of the composition of ashes in different 
parts of the same plant ? How illustrated ? What of ashes from 
different plants? Illustration. Explain Table III. What do the 
numbers at the top of each column represent ? From what source 
do plants receive their mineral ingredients ? 



ANIMAL C H E M I S T R if. 125 

CHAPTER VIII. 

ANIMAL CHEMISTRY. 

188. In studying the organic elements of plants, we have 
found the " starch group " most conspicuous. Vegetable 
fibre and starch make up the greater part of all ordinary 
ci'ops. But when we examine the composition of animals, 
we find a different group holding the first place. The 
'' proteine group " aids in the formation of almost every part 
of the animal system. These nitrogenized compounds con- 
stitute the greater part of the skin, the muscle, and the 
tendons. 

189. Let us now examine the composition and properties 
of the most important elements found in the animal kingdom. 

Proteine Group. — Several substances under different 
names, but very similar in composition, constitute this well- 
defined group. They are Fibrine, Albumen, and Caseine. 

190. Fibrine is the fibrous part of lean meat or muscle of 
animals. Exjieriments. — 1. Cut a few ounces of lean beef 
into small particles, and pour over the mass a little cold 
water; after allowing it to stand a few minutes, press the 
water out of it in a linen rag. Repeat this two or three 
times, and what is called ''flesh fluid" will be all washed 
out. Then boil the meat in a small quantity of water, and 
again press it as dry as possible in a cloth. The solid 
residue will be nearly pure y?&?-/?ie. 2. Heat the cold water, 
with which the meat was first washed, nearly to the boiling 
point ; a frothy mass will separate from it. This is albumen, 
which is soluble in cold water, but coagulates when the water 
is heated to 160° or 170°. 3. Set aside the small quantity 
of water, in which the meat was boiled, until it becomes cool, 

11* 



126 ANIMAL CHEMISTRY. 

and it will form a gelatinous mass. This is owing to the 
presence o^ gelatine extracted from the flesh by boiling water. 
Gelatine is soluble in boiling water, but when the water be- 
comes cold it becomes insoluble, and forms ^' jelly." 

191. Albumen is found in its purest form in the white of 
the Qg^, which consists of a solution of this substance in 
water. In a boiled e^^ the albumen is coagulated, and ren- 
dered insoluble. A solution of corrosive sublimate will co- 
agulate albumen, hence the value of raw eggs as an antidote 
for this dangerous poison. 

192. Caseine is most abundant in milk. When the 
cream has been removed from milk, the remainder is chiefly 
a solution of caseine. Exp. — Pour a little vinegar, or very 
dilute muriatic acid, into a tumbler of milk, and the caseine 
will be set free from solution, in the form of " curd." When 
milk becomes sour, through the formation of lactic acid, it 
curdles spontaneously. When the inner coating of a calf's 
stomach (rennet) is steeped in water, the solution has the 
property of separating the caseine from milk. When sweet 
milk is taken into the stomach, it is at once curdled by the 
acids of the gastric juice. Caseine pressed into cakes forms 
cheese. The oily matter (butter) from the milk is mingled 
with the curd, in making cheese from milk which has not 
been skimmed. 

193. The composition of these three principal proteine 
bodies of the animal kingdom is presented in the following 
table, according to Mulder's analysis : 

TABLE IV. 
In 100 parts. Fibrine. Albumen. Caseine. 

Carbon 54.56 54.84 54.96 

Hydrogen 6.90 7.09 7.15 

Oxygen 22.13 21.23 21.73 

Nitrogen 15.72 15.83 15.80 

Sulphur 0.36 0.G8 0.36 

Piiosphorus 0.33 0.33 



ANIMAL CHEMISTIIY. 127 

It will be seen that tliese substances closely resemble each 
other in composition, with the exception of the absence of 
phosphorus in caseine. 

194. Gelatine is a nitrogenized substance, already men- 
tioned (§ 190) as extracted from animal muscle by boiling 
water. It may be obtained much more abundantly from the 
bones, skin, tendons, and some other parts of the animal, by 
boiling them for some time. In the bones of young animals 
there is a large quantity of this compound, and compara- 
tively little mineral matter. Hence, calves' feet are a source 
of gelatine in the preparation of jelly. Common glue is a 
form of gelatine; it is dried jelly. Isinglass is dried gela- 
tine. One of its purest forms is found in the dried air- 
bladder of a species of fish. The gelatine from other animal 
substances is often dried and sold under the name of 
*' Isinglass." 

195. All animal, as well as vegetable compounds, con- 
taining ?NVro^c», pass very readily into a state of putrefaction, 
and emit a strong, disagreeable odor. This is especially the 
case with fibrine and albumen, which contain both sulphur 
and phosphorus. These form sulpJmretted a.ndi 2Jliosplmrettcd 
hydrogen, two gases which give the disgusting odor to rotten 
eggs and decaying meat. Carbonate of ammonia is also set 
free in large quantities by the decay of animal matter con- 
taining nitrogen. These bodies also induce decay, or fer- 
mentation, in other substances with which they are in con- 
tact. CooJdng coagulates albuminous substances, and makes 
their decay less rapid. Hence, cooked meat may be pre- 
served longer in warm weather than the same meat in a 
raw state. 

196. Gelatine forms an insoluble compound with tannic 
acid (§ 175), which may be kept an indefinite time without 
decomposition. Leather is such a compound. The gelatine, 
of which the skins of animals are chiefly composed, com- 



128 ANIMAL FATS. 

bines with tlie tannic acid of the bark used in tanning. 
Exp. — Dissolve a Uttle glue or isinglass in boiling water, 
and, before the solution gets entirely cold, pour into it a 
little water in which oak bark has been steeped. A pre- 
cipitate will be formed, which has the same composition as 
leather. 

197. Hoofs, horns, hair, and feathers, are similar in com- 
position to gelatine, having the addition of some sulphur. 

^ These forms are not converted into jelly by boiling, but they 
swell and become soft. They decay very slowly. 

ANIMAL FATS. 

198. The fats of ordinary animals used for food, consist 
chiefly of two compounds, called "Stearine" and '' Oleine." 
Another called "Margarine" is abundant in olive oil, and 
exists to some extent also in animal fats. Stearine is solid 
at ordinary temperatures, while oleine is fluid (oily). Mar- 
garine holds a medium place, being less solid than the 
former, and less liquid than the latter. Expi. — Take several 
pieces of thick wrapping-paper, six or eight inches square. 
Spread over one of them, with a knife, a thin layer of beef 
or mutton tallow. Lay a second piece of paper upon this, 
and give it a similar layer of tallow. Continue this, until 
several pieces are treated in the same way. Place the whole 
mass between two smooth boards, a little larger than the 
pieces of paper, and lay a heavy weight on the upper board. 
After an hour or two, separate the pieces of paper, and they 
will be found coated with a substance apparently drier than 
tallow. This is almost pure stearine. The oleine has been 
absorbed by the paper. 

Tallow and lard are both mixtures of steai'ine and oleine. 
Tallow has a larger proportion of stearine, and less oleine, 
than lard ; and is consequently more solid. 

199. Stearine and oleine arc compounds of two acids 



COMPOSITION OF PARTS OF ANIIMALS. 1C9 

called '^ stearic and oleic acids," combined with a compound 
base called " glycerine." When animal fats are boiled with 
caustic solutions of potassa or soda, these bases unite with 
the stearic and oleic acid, and form soaj^s. The potassa com- 
pound is soft soap, and the soda compound hard soap. The 
glycerine is set free, and remains partly mingled with the 
soap and partly in the refuse liquid. Lime and lead, with 
these fatty acids, form insoluble soaps. 

COMPOSITION OF DIFFERENT PARTS OF ANIMALS. 

200. Besides the substance above described, there are 
others which enter in small quantities into the various parts 
of the animal; and, where they seem important to a general 
view of animal chemistry, they will be mentioned in their 
appropriate connections ; but many of them must be passed 
over unnoticed. 

201. Skin, Hair, Horns, etc. — These have already 
been mentioned (§ 197), as being composed chiefly of gela- 
tinous matter. In the outer coating (epidermis) of the skin, 
a little sulphur is found ; and still more in the hair, horns, 
and hoofs, which may be regarded as appendages to the skin. 
The tendons, ligaments, etc., have a composition analogous 
to that of the skin. 

202. Flesh. — The solid part of the muscle, or flesh, has 
been described in § 190 as being composed of a proteine 
substance called '' fibrine." It has an organized structure, 
and is insoluble in water. In acetic acid, or strong vinegar, 
it dissolves to some extent. If potassa solution be added to 
the acetic acid in which a piece of flesh has been digested 
for some time, the dissolved fibrine will be precipitated, and 
give the liquid a turbid appearance. 

203. There is some fat mingled with the fibrine in the 
muscular part of nearly all animals; but about 80 per cent 
of the weight of fresh, lean muscle, consists of a fluid called 



130 COMPOSITION OF PARTS OF ANIMALS. 

''flesh -fluid." It holds albvmen in solution; but when 
heated nearly to the boiling-point of water, this albumen is 
coagulated. The flesh-fluid also contains an acid, and some 
other substances, which give peculiar flavor to meats, and to 
soups prepared from them. If the water in which fresh 
meat is to be cooked, is heated to the boiling-point before 
the meat is put into it, the albumen near the outer surface is 
at once coagulated ; and other portions, as they come near 
the surface, or as the heat penetrates the mass, are also coag- 
ulated ; and in this way much of the highly flavored and 
nutritious juice of the meat is prevented from escaping. But 
if the object is to get a broth or soup containing as much as 
possible of the richness and flavor of the meat, the heat 
should be very gradually applied to the water after the meat 
has been placed in it. 

The most abundant mineral matter in flesh-fluid consists 
of salts of potassa ; but the potassa is not sufficiently abun- 
dant to neutralize all the acids of the fluid, for it is found 
always to be acid in its character. 

204. Bones form the framework of the animal. They 
contain an organized form of (jclatinous matter, associated 
with a large quantity of mineral matter, which is chiefly 
phosjjhate of lime, with a little carbonate of lime; and in 
some parts of the bones, a trace of fluoride of calcium is 
found. 

Experiments. — 1. Boil a fresh bone for some hours in 
water. Evaporate the water to a small quantity, and set it 
aside in a cool place. The solution soon becomes jelly. 2. 
Throw a bone into the fire, and let it remain some time, and 
it will become white when cool. The gelatinous matter will 
then be burnt out, and the remainder (bone-earth) is chiefly 
p1ioq)]iate of lime (oCaOjPOs), with some carbonate of lime, 
and a little of other salts. 3. Burn a bone in a covered cru- 
cible, or small iron pot. The air being thus excluded, the 



COMPOSITION OF PARTS OF ANIMALS. 131 

heat will char the organic part without consuming it ; and 
the result will be hone-blach (ivory-black). 4. Pour dilute 
muriatic acid over a bone, and set it aside for a day or two ; 
the phosphate of lime will be dissolved out by the acid, and 
the gelatine will be left as a soft elastic mass, having the 
same form as the bone. When washed and boiled, this gela- 
tine will be dissolved, and form glue. 

Bones possess a very high value for fertilizing purposes, 
as we shall learn in another chapter. 

According to Berzelius, 100 parts of the bones of an ox 
consist, — of animal matter, 33.30; phosphate of lime, and a 
little fluoride of calcium, 57.35; carb. of lime, 3.85; phos. 
of magnesia, 2.05; soda, with some chloride of sodium, 3.45. 

205. Nervous Matter, of which both the brain and 
nerves are composed, is a mixture of albuminous matter with 
some peculiar oily substances. 

206. Blood. — If fresh blood is stirred for some time with 
a bundle of small rods or twigs, a fibrous substance will be 
found adhering to the rods. When washed in clean water, 
this substance becomes nearly white. It is animal fihrine, 
having the same composition as muscle. But if blood is 
allowed to stand for a short time without being stirred, it coag- 
ulates, or forms a clot. After standing for some time, a color- 
less liquid separates from the clot. This liquid is called the 
" serum," and is a solution of albumen. When heated to a 
boiling temperature, the albumen is coagulated. 

The coloring matter of blood consists of small globular 
bodies, called " blood corpuscles," which are diffused all 
through the blood when in the veins ; but, after exposure to 
the air for a short time, these corpuscles are separated, and, 
becoming entangled with the fine threads of fibrin e, form the 
clot. 

The chief constituents of blood are water, Jibrine, albu- 
men, and corpuscles. 



132 COMPOSITION OF PART 8 OF ANIMALS. 

207. Mineral salts are found in the blood; chiefly common 
salt and phosphate of soda, with some sulphates of soda and 
potassa. Iron is found in considerable quantity in the color- 
ing matter. 

The different conditions of the blood, effects of respira- 
tion, and the functions performed by the blood, will be found 
under the head of Animal Physiology. 

208. Digestive Fluids. — These are the saliva, gastric 
juice, pancreatic fluid, and hile. 

209. Saliva is a slightly alkaline fluid, secreted by the 
glands of the mouth. It is water holding*in solution a little 
organic matter, with some alkaline phosphates and chlorides. 

Gastric juice is secreted from the inner coating of the 
stomach (mucous membrane). It contains a little hydro- 
chloric acid in solution, also some lactic acid. These give it 
an acid character. There is a peculiar organic substance 
found in gastric juice, called '^pepsin." * This substance, 
obtained from the stomach of the ox, is often employed as a 
medicine, in cases of dyspepsia. The gastric juice holds 
common salt in solution, with small portions of other salts. 
The acid character of this fluid gives it the power of dis- 
solving (digesting) fibrine, albumen, and other forms of pro- 
teine matter. 

210. Pancreatic fluid is an aJkaline secretion, from a 
peculiar organ near the stomach called the " pancreas." 
This fluid is mingled with the food as it passes out of the 
stomach into what is called the " duodenum." It has the 
power of digesting starch and oily compounds. 

211. Bile is a secretion from the liver, and is alkaline. 
It is thrown into the duodenum with the pancreatic fluid, 
but physiologists difibr as to the office it performs in diges- 
tion. It is supposed to aid especially in the digestion of 
fatty substances. 

* From pepto, " digest." 



MILK. 133 



JM ILK. 



212. Milk has been mentioned (§ 192) as the chief source 
of caseine. Besides caseine, it contains little globules of 
o% matter (butter'), and a peculiar kind of sugar, called 
" sugar of milk," or " lactose." The method of separating 
caseine has been already given. If the clear ivhei/, left after 
the caseine is removed, be evaporated to dryness, a mass of 
crystalline sugar will be obtained (see § 141). When milk 
becomes sour, this sugar is converted into lactic acid. 
Churning consists in simply agitating the milk so as to cause 
the little globules of butter to unite into masses of sufficient 
size to be easily separated from the liquid. Butter is com- 
posed chiefly of two fats : olcine, which is oily at common 
temperatures, and margarine, which is solid. When exposed 
to the air for some time, butter becomes rancid, by a portion 
of volatile acid being generated in it, which gives it a dis- 
agreeable taste and odor. It may be again sweetened, at 
least to some extent, by boiling it several times in two or 
three times its own volume of water, or by careful washing 
with fresh milk. 

213. Ashes of Milk. — When milk is evaporated to dry- 
ness, one hundred ounces of it will yield about 12J ounces 
of solid matter. About 87 2 ounces of water have disap- 
peared, while caseine,- butter, sugar, and mineral matter are 
left. If you now burn this 12 5 ounces of solid matter to 
ashes, the caseine, butter, and sugar, will disappear, being 
all decomposed and expelled by the heat. The ashes left 
will weigh about a half-ounce. That is, one hundred ounces 
of milk contain about a half-ounce of mineral matter. Nearly 
the half of this mineral matter is plios^jhate of lime, a little 
more than one-fourth of it is chloride of potassium, while 
the remainder is made up of phosphate of magnesia and salts 
of soda and iron. Milk contains just those elements best 

12 



134 EXCREMENTS. 

fitted to promote tlie growth of the young animal for whose 
nourishment an all-wise Creator designed it. 



EXCREMENTS. 

214. The refuse portions of the food, and the waste matter 
of the animal system, are thrown oif partly in a solid and 
partly in a liquid form. The solid excrements (faeces) con- 
sist, for the most part, of those constituents of the food which 
are not dissolved in the stomach — not digested ; in the her- 
bivorous animals, they consist principally of vegetable tissue, 
chlorophyll, wax, and insoluble salts; in the carnivorous 
animals, dogs for instance, frequently almost wholly of inor- 
ganic substances, as phosphate of lime, magnesia, &c., mixed 
with but a very small quantity of organic matter. The bene- 
ficial influence of solid excrements on vegetation is princi- 
pally owing to the inorganic compounds contained in them 
(lime and magnesia, phosphoric acid and silicic acid). 

215. By the urine, which is separated in the kidneys from 
the arterial blood, the soluble salts contained in the food, and 
also the nitrogen compounds, no longer necessary for the vital 
process, are removed again from the body; it is natural, there- 
fore, that the constituents of it, as likewise of the faeces, 
should correspond exactly with the food consumed. If this 
is rich in soluble salts, the urine will- also be rich in them j 
if this contains only a few soluble, and many insoluble salts, 
the urine will be poor in soluble salts, while the foeces will be 
rich in insoluble salts. Consequently the amount of inorganic 
substances in the animal excrement, or manure, may be just 
as accurately ascertained from the food which the animal con- 
sumes, as from the manure itself. The food has only to be 
burned, and the remaining ashes examined ; those parts of 
it which are soluble in water, correspond with the salts of 
the urine; those which are insoluble, to the salts of the 



EXCREMENTS. 135 

fseces. We find in the urine of cows and horses principally 
alkaline carbonates, muriates, and sulphates of potassa, soda, 
and ammonia ; in the urine of men, moreover, some alkaline 
phosphates. 

216. ^'Nitrogen is contained in the urine, either in the 
form of urea, uric acid, or hippuric acid. Urea occurs iu 
the greatest abundance in the urine of the higher animals, 

especially the carnivorous quadrupeds In a 

practical point of view, that decomposition which urea 
undergoes in urine, when the latter putrefies by long standing 
in the air, is of great importance. During this decomposi- 
tion, the urea combines with the constituents of two atoms 
of water, and becomes thereby carbonate of ammonia; from 

Urea = Carbon, Oxygen, Nitrogen, Hydrogen ; 

and Water = Oxygen Hydrogen 

are formed, ""p; — r -. r^ , ""^^'^T^""" "^""^ 

Carbonic acid and Ammonia. 

217. " Uric acid (lithic acid) predominates in the urine 
of the lower animals. The white excrements of birds and 
snakes (a mixture of fasces and urine,) consists chiefly of 
urate of ammonia. In the pure state it consists of fine 
white crystalline scales, which are dissolved in water only 
with extreme difficulty. On account of this difficult solu- 
bility, it sometimes separates spontaneously from the urine, 
as gravel and urinary calculi. If the excrements, which are 
rich in uric acid, are allowed to remain for some time exposed 
to the air they will absorb oxygen, and afterwards contain 
oxalate of ammonia; but if the latter takes up more oxygen, 
it passes over into carbonate of ammonia. Thus is explained 
the cause why we frequently find in some sorts of guano 
only traces of uric acid, but in place of it, large quantities 
of oxalates. 

218. ^^ Guano, which in recent times has been in such 
demand as a manure, owes its efficacy chiefly to the iiric acid 



136 EXCREMENTS. 

(as urate of ammonia) contained in it ; or, in as far as this 
lias already undergone decomposition, to the ammoniacal 
salts formed from it, and in part also to inorganic salts (sul- 
phate, phosphate, and muriate of potassa, soda, lime, magne- 
sia, &c.) present in it. On account of the great difference 
in the article, it is indispensable that the firmer should test 
it before its application. This is done with sufficient accu- 
racy for agricultural purposes in the following ways : 

Experiments. — a. Pour some strong vinegar over guano; 
no perceptible eff'ervescence should ensue. A brisk effer- 
vescence would indicate an admixture of carbonate of lime. 
h. Heat half an ounce of guano in an iron spoon, over an 
alcohol lamp or over glowing charcoal, till it is burnt to 
white ashes ; good guano should only leave behind, at most, 
one dram (l ounce) of ashes. How much alkaline salts this 
ashes contains, may be ascertained by extraction with hot 
water; what remains (undissolved) are lime and magnesian 
salts. The inferior sorts of guano often yield, after burning, 
three-quarters of ashes, c. Treat an ounce of pulverized 
guano several times with hot water, and decant the liquid 
after it has become clear on settling; then dry and weigh 
the muddy mass which finally remains ; it should not weigh 
more than half an ounce. 

219. "Sijyjmn'c Acid. — This azotized acid always occurs 
in the urine of herbivorous animals : it crystallizes in long, 
white needles, and is difficultly soluble in water. On the 
putrefaction of the urine, it is converted into benzoic acid 
and ammonia. 

" Human urine contains the above-named compounds (rich 
in nitrogen) — urea, uric acid, and hippuric acid; the first 
(urea) in the largest quantity. 

2!Z0. 'MVhen urine remains for some time exposed to the 
air, it undergoes a decomposition, by which volatile sub- 
stances having a disagreeable odor are formed : it passes 



QUESTIONS. 137 

into i^utrefaction. It is obvious, from what Las been stated, 
that carbonate of ammonia is to be regarded as the principal 

product of this decomposition This change takes 

place when the urine is collected in manure heaps, or is 
poured upon the soil. To prevent the escape of the volatile 
carbonate of ammonia, it is best to add gypsum, dilute sul- 
phuric acid, etc." — Stochhardt. See also §378. 



QUESTIONS ON CHAPTER VIII. 

§ 188, 189. What group of proximate constituents did we find 
most conspicuous in the chemistry of plants? What group is most 
conspicuous in animal chemistry ? The most important substances 
of the proteine gr»up ? 

190. What is /6?en€ .^ First experiment? second? third? 

191. What is albumen? Influence of heat upon it? 

192. Where is caseine most abundant? How separated? Effect 
of rennet on milk ? Of the acid juices of the stomach? AVhat is 
cheese ? 

193. What does Table IV represent ? IIoav do these substances 
differ ? 

194. 195, 1 96, 197. What is gelatine ? What of the bones of young 
animals? What is glue? Isinglass? What of the putrefaction of 
animal bodies? What substances are set free ? Influence of decay- 
ing animal matter on other substances? How does cooking prevent 
putrefaction? What is the chemical process in tanning? IIow illus- 
trated? AVhat of hoofs, horns, etc.? 

198, 199. Of what are fats of ordinary animals composed? Pro- 
perties of stearine and olcine? How separated? Of what are tallow 
a,nd lard composed? How do they differ? What is the chemical 
composition of stearine and oleino? How are soaps formed? Soft 
soap and hard soap ? Soaps of lime and lead? 

200, 201. Of what are skin, hair, and horns composed? What of 
sulphur in these? Tendons and ligaments? 

202, 203. Of what is the flesh of animals composed? Its struc- 
ture? Effect of acetic acid upon it? How precipitated? What 
is mingled with fibrine in the muscles ? What constitutes the greater 
part of the weight of fresh lean meat ? Composition of flesh fluid ? 
12* 



188 QUESTIONS. 

What of cooking meat? — making soup? Most abundant mineral 
substance in flesh fluid? 

204, 205. Describe the bones of animals. First experiment? se- 
cond? third? fourth? For what are bones valuable? Composition 
of an ox-bone? What is nervous matter? 

206, 207. IIow may fibrine be separated from fresh blood? AVhen 
does blood coagulate? Wliat is the serum? Coloring matter of 
blood ? Chief constituents of blood ? Mineral salts ? 

208, 209, 210, 211. What are the digestive fluids ? Describe saliva. 
Gastric juice ? For what is pepsin used ? Describe the pancreatic 
fluid. What substances are digested by it ? Secretion of bile ? Its 
office? 

212, 213. Chief solid constituent of milk? What is butter? How 
is sugar of milk obtained? Explain the souring of milk. What is 
churning? How does butter become rancid ? How may it be sweet- 
ened ? How much solid matter in milk ? How much ashes in milk? 
Chief mineral constituent? For what is millc peculiarly fitted? 

214, 215, 216. Office of the urine? How is its composition in- 
fluenced by food ? Chief salts in the urine of cows and horses ? 
What substances in urine contain nitrogen? What changes take 
place in the putrefaction of urine ? What are the products ? Ex- 
crement of birds ? 

217, 218. Properties of uric acid? Result of the decomposition 
of urate of ammonia? Most valuable ingredient in guano? j\Iine- 
ral salts of guano ? Experiment a ? Experiment b ? Experiment c ? 

219, 220. AVhere is hippuric acid found? What of human urine? 
Its putrefaction ? How may its carbonate of ammonia be preserved ? 



SOURCES or PLANT K O U U I S II .^I E K T. 139 



CHAPTER IX. 

SOURCES FROM WHICH PLANTS DERIVE 
THEIR NOURISHMENT. 

221. It has been stated (in §132) that plants are com- 
posed of two sets of elements : (1) The " organic elements," 
which are volatile, and disappear during combustion ; (2) 
The " inorganic or mineral elements," which are incombus- 
tible, and constitute ashes. These two classes seem equally 
necessary to the healthy growth and full development of the 
plant. They constitute the food of the plant, as they are 
taken up by it while growing. 

222. Sources of Plant Food. — Plants do not get all their 
food from the soil on which they grow, as many persons 
suppose. The soil and the air both furnish nourishment 
to the growing crop. Through its roots, the plant is in 
constant contact with the soil, and through its leaves it 
is in constant contact with the air. The roots are so con- 
structed as to be able to absorb from the soil such food as is 
required from that source, whenever it is found there in a 
proper condition. But all substances taken up by the roots 
must be first rendered soluble, as these organs can absorb 
matter only in the liquid form. 

223. The mineral elements, being involatile, are not found 
in the air ; hence, they must be derived from the soil alone. 
Besides these, the soil must have a sufficient quantity of 
water to dissolve whatever is required by the plant. The 
soil also contains, generally, a considerable quantity of or- 
ganic matter, the use of which we shall see in the next 
section. 



110 SOURCES OF PLANT NOURISHMENT, 

224. Wheyice do ]il«nts get their organic demerits? These 
have been stated to be chiefly four — carbon, hydrogen, oxy- 
gen, and nitrogen. The carbon of plants is derived chiefly 
but not entirely, from carbonic acid. This gas is one of the 
constituents of the atmosphere, and is found to make about 
the j-soo part of the weight of air, whether this air be col- 
lected in the lowest valley or on the top of the highest 
mountain. Plants have the power of collecting carbonic gas 
from the air through their leaves. As the organic matter in 
the soil undergoes decay, this gas is freely generated, and, 
being absorbed by the water of the soil, is conveyed abun- 
dantly to the roots of the growing plant. As rain descends 
through the air, it absorbs a considerable quantity of car- 
bonic gas, and conveys it to the soil. Thus we find both the 
atmosphere and the soil to be sources of this carboniferous 
food. Whether the carbonic acid be absorbed by the roots 
or by the leaves, it circulates through the plant in solution 
in the sap; and under the influence of light it is decomposed, 
the plant retaining the carbon, and throwing oif the oxygen 
through the leaves. This action goes on chiefly by day, and 
most rapidly under the direct rays of the sun. Hence, plants 
grow more rapidly by day than by night. If light be ex- 
cluded entirely, the plant soon dies. 

The hnmus of the soil, or rather some of its constituents, 
become soluble in certain combinations. In this form, too, 
carbon is doubtless taken up by the roots, and conveyed 
through the sap to the diff"erent parts of the growing plant. 

225. Hydrogen and Oxygen are supplied to plants in the 
form of loater. If you look back over the vegetable com- 
pounds which we have studied, you will find a large part of 
them containing H and in the proportions in which these 
exist in water. Take, for example, starch (CuHioOio). Here 
we find the elements of ten atoms of toater. In the forma- 
tion of such a compound as starch, twelve atoms of carbonic 

*Also written (Cj^IIjoOjg), 



SOURCES OF PLANT NOURISHMENT. 1-41 

acid must be decomposed, and tlieir carbon combined with 
ten atoms of water, to form one atom of starch. The leaver 
absorb yfdXGV from the air ; the roots absorb it from the soil. 

226. Nitrogen is not so abundant in plants, as the other 
three organic elements; but it is not less important, and even 
essential, to their growth. Ammonia (NH3) is no doubt the 
chief source from which plants get their nitrogen ; and some 
chemists believe it to be the only form in which nitrogen is 
taken into the growing plant. But nitric acid (in the ni- 
trates), and several other nitrogen compounds, are doubtless 
sources from which this important element is often derived. 
Prof. Johnston says : '' There seems, indeed, very little solid 
foundation for the opinion held by some, that the plants in 
our cultivated fields derive the ichole of their nitrogen from 
ammonia and nitric acid together — still less, that they obtain 
it from ammonia alone." Still, ammonia is the great source 
.of nitrogen to the vegetable world. 

227. Ammonia is found both in the atmosphere and the 
soil. From the atmosphere it is carried down by rain 
and snow. In the soil it is generated by the decay of 
such animal and vegetable compounds as contain nitrogen. 
It is retained by the clay, as well as by the humus of the 
soil (see § 367). Some plants are believed to absorb it 
from the air, through the leaves ; but in most cases it enters 
through the roots from the soil. Although nitrogen is so 
abundant as the chief constituent of our atmosphere, it 
rarely (perhaps never) enters directly in its pure, gaseous 
form, into any of the combinations in which it occurs in 
organic substances. In contact with decaying organic matter 
in the soil, and in other closely confined localities, nitrogen 
from the air unites with nascent hydrogen, forming ammonia. 
The ammonia formed in this way, as well as that which is set 
free by the decay of proteine matter, may be again decom- 
posed in the presence of strong bases, such as lime and alka- 



142 QUESTIONS. 

lies ; the nitrogen of NH3, becoming oxidized, forms nitric 
acid (NO5), "while the hydrogen, combining with an addi- 
tional quantity of oxygen, becomes water. The nitric acid 
thus generated combines with whatever bases may be present, 
forming nitrates. " Nitre (nitrate of potassa) is often gene- 
rated in arable land, whence it passes into the juice of 
plants ; thus it is known that beets and tobacco, growing 
upon very strongly manured soil, and also those rank plants 
growing on manure heaps, such as henbane, thorn-apples, 
etc., are frequently so rich in nitre, that when dried they 
emit sparks, if burnt on charcoal. 

" Nitric acid is also naturally formed, and in some coun- 
tries probably in large quantities, by the passage of electricity 
through the atmosphere. The air consists of oxygen and 
nitrogen mixed together; but when electric sparks are passed 
through a quantity of air, minute portions of the two gases 
unite together chemically, so that every spark which passes 
forms a small portion of nitric acid. A flash of lightning is 
only a large electric spark; and hence every flash that crosses 
the air, produces along its path a sensible portion of this 
acid. Where thunder-storms are frequent, much nitric acid, 
and probably some ammonia, are produced in this way in the 
air. They are washed down by rains — in which they have 
been frequently detected — and thus reach the soil, where the 
acid combines with potash, soda, lime, etc." — {Johnston.^ 

228. The soil and the air, then, are the great fountains of 
nourishment for the vegetable world. The soil provides 
mineral matter, carbonic acid, humus, water, ammonia, and 
nitric acid. The air, too, provides all these except mineral 
matter and humus. 

QUESTIONS ON CHAPTER IX. 

221, 222, 223. Of what two classes of elements are plants com- 
posed ? Are they equally necessary ? Do plants get all their food 



QUESTIONS. . 113 

from the soil ? From -what other source? How are plants brought 
in contact with their sources of nourishment ? Are the mineral 
elements found in the air? In what condition must they be when 
taken up by the roots ? 

224. Whence do plants get their Carbon? Is carbonic acid abun- 
dant in the atmosphere? How collected by plants? How does 
organic matter in the soil furnish food to plants ? AVhat change 
takes place on carbonic acid in the organs of the plant? What if 
light be excluded from a plant? How does Humus furnish food for 
plants? 

225. In what form are Hydrogen and Oxygen supplied to plants ? 
Do they constitute a large proportion of vegetable compounds? 
What is the composition of starch ? 

226. Is Nitrogen as abundant as other organic elements ? Chief 
source of nitrogen? From what other source may it also be derived? 

227. 228. Where is Ammonia found ? How does it reach the roots 
of plants ? How generated in the soil ? How retained ? Is nitro- 
gen ever absorbed dii-ectly from the atmosphere? How may ammo- 
nia be converted into nitric acid? What plants contain nitrate of 
potassa ? How is nitric acid generated in the atmosphere ? What 
do the soil and air respectively provide for the plant ? 



1 U V E r, E T A B L E T 11 Y S I O L O G Y. 



CHAPTER X. 

VEGETABLE PHYSIOLOGY. 

229. Plants and animals constitute the two great depart- 
ments of organic nature. They all consist of those organs 
necessary to sustain life, to promote growth, and to repro- 
duce their own species. Plants, as well as animals, are en- 
dowed with vitalif//; hut they differ from animals in not 
possessing sensation. In some plants there seem to be some 
evidences of sensation, as in the sensitive plant (^Mimosa')', 
and it may be that all plants have some kind of sensation, 
which is so obscure as not to be ordinarily perceptible. Still 
we generally regard plants as destitute of this property. 

230. Botany is the science of plants. It gives us a know- 
ledge of their names, classification, structure, the functions 
of their various organs, and the uses to which the}^ are 
applied. 

231. Vegetable Physiology is that department of 
Botany which treats of the organs of plants — their structure, 
and the part they severally perform in promoting life and 
reproduction. A distinction is drawn between vegetable 
Anatomy and Physiology; the former treating of the struc- 
ture of the organs, and the latter of their functions. But 
we shall embrace both of these in the term Physiology. An 
intelligent vicAV of this subject is of high importance to 
every one engaged in the cultivation of the soil. 

232. Skilful cultivation always increases the productive- 
ness of plants; and, in many cases, improves their quality to 



VEGETABLE P II Y S I L O O Y. 145 

such an extent as to render what was once worthless, now 
highly valuable. The apple, the potato, and the tomato, are 
examples of plants reclaimed from a wild and almost worth- 
less state, to one of the highest value and importance. 

233. Germination. — The plant is first found as an cm- 
hryo in the seed, from which it springs. Exp. Place a bean 
in warm water, and let it remain a few hours, until it becomes 
swollen. Then separate the two lobes of which it is formed, 
and you will discover, near what is called the '' eye" of the 
bean, the embryo, consisting of two parts, one to be deve- 
loped into roots, and the other into the stalk and leaves of 
the plant. 

When a seed is placed in a moist, warm soil, it soon begins 
to absorb water, and also oxygen from the air mingled with 
the soil. A chemical change begins at once within the seed, 
by which the material of the grain is so modified as to be- 
come the food of the embryo plant. Seeds consist chiefly of 
starch and gluten; but these being insoluble, cannot be taken 
up by the germ in their present form. Under the combined 
influence of air, water, and heat, the gluten becomes diastase, 
and begins to act as a ferment (§ 138) ; and, under its influ- 
ence, the starch is soon converted into dextrine, and then 
into sugar. Being thus rendered soluble, it enters the cir- 
culation of the embryo, which begins to expand, and soon 
bursts the seed. It " sprouts," sending forth two branches, 
one of which turns downward, and puts forth roots ; this is 
called the radicle. The other turns upward to seek the light 
and air; this is thep?wmif?e, and is soon developed into the 
stalk and leaves. Exp. Put grains of corn into several cups 
or bowls filled with fine soil, and place them in a warm 
place for three or four days, keeping the soil moist. At the 
end of this time examine one of them, and observe the 
change the grain has undergone. Then examine one on each 
successive day, and you will see the radicle and idumide 
18 



14G 



VEGETABLE T II Y S I O L O O Y. 



in their various degrees of development, until the one he- 
FiG. 30. comes roots, and the other rises to the sur- 

face, and sends forth a green blade. Mean- 
while the grain has been consumed, and will 
soon disappear entirely; the plant being now 
able to get nourishment from the soil through 
its roots, and from the air through its blades 
or leaves, no longer requires the store of 
nourishment which an all-wise Providence 
had laid up for its inflmcy. Fig. 30 will 
give some idea of the appearance of a grain 
of Indian corn, in one of its stages of germi- 
nation. 

The covering of the seed is called the 
integument (the bran); the starchy part 
within the integuments, and surrounding 
the embryo, is known as the albumen. The 
albumen and integuments together form what 
is called the cotyledon, or seed-lobe. When a seed consists 
of only one lobe or cotyledon, the plant producing it is said 
to be monocotyledonous : Indian corn is an example of a 
monocotyledonous plant. If the seed has two lobes, as the 
bean, the plant is dicotyledonous. 

234. The stems of plants whose seeds have only one coty- 
ledon, increase in size by internal growth. Such plants are 
called Endogens. The dicotyledonous plants, on the other 
hand, generally grow by the formation of new layers on the 
outer part of the stem, and immediately beneath the bark. 
They are hence called Exogens. The grasses (including 
wheat, corn, etc.), the palms, and plants generally having 
the veins of their leaves parallel, are endogens. Beans, 
peas, and the trees and shrubs of our forests, are exogens. 

235. Tissues of Plants. — The various organs of plants 
are composed chiefly of several kinds of structure, called 




VEGETABLE PIIYSIOLOOY. 



147 



Fig. 31. 



m 



tissues. These are made up of Jibres or membranes, or both 
together. 

There are five kinds of tissue: 1. Cellular tissue; 2. 
Woody tissue; 3. Vascular tissue; 4. Vasi/orm tissue; 5. 
Laticiferous tissue. 

236. Cellular tissue is composed of minute cells, resting 
upon and pressing against each other, so that the sides where 
they meet become flattened, 
and give to the cell a some- 
what regular form. Fig. 31 
(a) is a section of cellular 
tissue from pith of elder, as 
viewed with the microscope. 

237. Woody tissue has a 
fibrous structure — the fibres 
being in the form of slender 
tubes overlapping each other 
at their extremities, as in Fig. 
31 (b). It is this structure 
which gives strength to wood, 
and the various kinds of fibrous 
material used in the arts, such as flax, hemp, cotton, etc. 

238. The vascidar tissue resembles the woody in external 
form, but difiers in having a long slender fibre coiled within 
it from end to end. 

239. The vasi/orm tissue consists of tubes much larger 
than those of the woody fibre. These tubes may be seen in 
a cross-section of oak-wood. It is chiefly through these that 
the sap passes in ascending from the roots to the leaves. 

240. Laticiferous tissue consists of very small tubes and 
cells, found most abundantly in the bark and leaves. After 
the sap has been prepared in the leaf for nourishing the 
plant, it is called latex. Those vessels of the leaf in which 
this preparation or elaboration goes on, and those which 




148 QUESTIONS. 

afterwards convey the latex to the part of the plant to be 
nourished by it, are formed of the latieiferous (latex) tissue. 

These various kinds of tissue hold and transmit the fluids 
of the plant, the different tubes and cells having no com- 
munication with each other, except through minute pores. 
These vessels are sometimes charged with liquid matter, and 
sometimes with gases. 

Let us now examine the structure and functions of the 
various organs so beautifully constructed out of these several 
forms of tissue. 



QUESTIONS ON CHAPTER X. 

§ 229, 230, 231. In what respect are plants and animals similar? 
How do they differ? What is Botany? Vegetable Physiology? 

232, 233, 234. How does cultivation influence plants ? Examples. 
Where is the germ of a plant found ? Experiment. When a seed is 
placed in moist, warm soil, what change takes place ? How does the 
material of the seed nourish the embryo plant? What is the radi- 
cle? Plumule? Experiments with a grain of corn? The integu- 
ments of seeds ? The albumen ? Cotyledon ? What plants are called 
Undogens ? Exogens ? Examples ? 

235 — 240. Of what are the organs of plants composed? How 
many kinds of tissue? What are they? Describe cellular tissue? 
Woody tissue. Examples. Vascular tissue. Vasiform tissue. 
Where seen? Latieiferous tissue? What part do these tissues 
perform ? 



OEGANS OF PLANTS. 149 



CHAPTER XI 

ORGANS OF PLANTS. 

241. The chief organs of the plant are the Barh, Roof, 
Stem, Leaf, and Floiccr. 

242. Bark. — The hark is the external covering of the 
plant; and, in the widest sense, may be regarded as enve- 
loping every other part of it, except the extremities of the 
roots, and the stigma of the flower. It consists of three 
layers. The outer one, called the Epidermis, is a thin, and 
often transparent integument, which covers every part of the 
plant, with the exceptions above mentioned. It may be 
easily separated from the surface of the leaves and green 
stems of many plants. On trees of many years growth, it 
becomes thick and rough, forming an uneven, scaly surfoce. 
The inner layer of the bark, which is in contact with the 
surface of the wood, is called the liber. It is generally thin, 
and often strong enough to serve many valuable purposes of 
art. The ancients used it as we use paper (hence, liber, a 
book) ; while in more modern times it has been used in the 
manufacture of mats, and of cloth of various qualities, from 
the coarsest coflFee-sack to the finest Irish linen. Between 
the epidermis and liber is the cellular integument, which in 
many trees is quite thick. In the bark of the cork-tree 
{Quercus suber,') it forms the material of which corks are 
made. 

The epidermis and cellular integument are both composed 
chiefly of cellular tissue. The liber consists of cellular and 
woody tissues. 
13* 



150 



BOOTS. 



There are little openings in the epidermis, called stomata 
(mouths). These are very minute, requiring the aid of the 
microscope to see them. They are most numerous on the 
surface of the leaves, and on parts of the plant of recent 
growth. These stomata perform important offices, which will 
be discussed in connection with the leaves. 

243. Glands are minute masses of cellular tissue, of 
various forms, and situated in different parts of the plant. 
Their office is to elaborate and discharge the peculiar secre- 
tions of the plant. The gums, oils, &c., are secreted by 
glands. 

Hairs, stings, and prickles, are protuberances of the epi- 
dermis, or of the cellular integuments, covered by the 
epidermis. 

ROOTS. 

244. The roots serve the double purpose of sustaining the 
plant in its proper position, and of absorbing from the soil 
appropriate nourishment. Their office is somewhat similar 
to that of the mouths of animals. They take in both food 
and water. 

245. Variety of forms. — Roots have a great variety of 
form, but we have room to notice only a few of the most 

common and conspicuous 
varieties. (1.) The ra- 
mose, or branching rooty 
is one which sends off 
branches of various size 
in every direction. It is 
the kind of root common 
to all trees and shrubs. 
(See Fig. 32, a). (2). 
The spindle root tapers 

from the top downward, often branching near the lower end. 

It sends off little branches, or rootlets, all along the sides. 



Fig. .32, a. 




ROOTS, 



151 



V 



Fig. 32, c. 



We have examples of this form in the radish and parsnip 
(Fig. 32, J). The tiirnijy, or naivfortn root, differs from 
the spindle root, only in swelling out consider- 
"' ' ably, just at the surface of the ground. (3.) 
The tuberous root consists of fleshy masses con- 
nected together by fibres. It closely resembles 
the potato, which was formerly regarded as a 
tuberous root; but the proper tuberous root 
has no buds (eyes), while the potato has, and 
it is, therefore, classed with underground stems. 
I ^ ■■ M ('^■) The fibrous root is one 
[iW_:S which consists of nume- 
rous thread-like divisions, 
or fibres, extending out 
from a common head near 
the base of the plant. 
Wheat, corn, and most of 
the other grasses have 
fibrous roots (Fig. 32, c). 
Other varieties we cannot now stop to notice. 
The student should collect the different varieties of roots, 
and wash them carefully, so as to preserve every part un- 
broken, that he may become familiar with them as they 
actually grow. 

245. Floating, or aquatic roots, are such as belong to plants 
which float upon the surface of water, without having any 
connection with the soil. 

246. Aerial roots are such as shoot forth in the air. (1.) 
Sometimes they remain suspended in the air, without attach- 
ing themselves to any other substance, except so far as may 
be necessary to sustain the plant to which they belong. 
Their ofl&ce, then, is to absorb nourishment from the air, and 
the rain which falls upon them. Of such plants are the 
pendent mosses, which festoon the trees so remarkably in 




152 ROOTS. 

some of our Southern States. (2.) They sometimes attach 
themselves to the bark, and even penetrate the tissues of 
other plants, from which they get their nourishment. The 
mistletoe is an example of such beggar-plants. They are 
aptly called "jmrasites." (3.) The roots which shoot forth 
from the joints of some prostrate plants, as the tomato, are 
regarded as aerial roots, but these soon penetrate the soil. 
(4.) Another variety of aerial roots are such as spring from 
the stems of erect plants, at some distance above the surface 
of the ground, and extending downward into the earth, stand 
like a circular row of braces around the base of the stalk. 
We have a beautiful example of this kind of root in the 
Indian corn, when growing on a good soil. These are often 
called brace-roofs. They serve to support the plant, and 
prevent its being prostrated by winds; and, at the same time, 
collect nourishment from the soil. 

247. Parts of the root. — Whatever may be the shape of 
the root, it generally has several distinct parts worthy of 
notice : 

(1.) The Caudex is the main body of the root, generally 
descending vertically into the soil. It is frequently called 
the tap-root. 

(2.) The Fibrils are the branches sent off from the caudex, 
often passing into many sub-divisions. 

(3.) Sjionffioles are the soft, pulpy points of the fibrils, 
through which the plant gets its nourishment from the soil 
in a liquid form. 

248. Structure. — The root has a structure similar to that 
of the stem to which it belongs. The bark of the root is 
more soft and spongy than the bark of the stem. Its epi- 
dermis terminates near the spongioles, leaving them un- 
covered. The fibrils are composed chiefly of vasiform tissue, 
covered with the epidermis. The extremities of the fibrils 



THE STEM. 153 

consist of this vasiform tissue in very soft and delicate form, 
spongy in structure, and hence called " spongioles." 

249. Functions of the Root. — These have several times 
been alluded to. The, first is the mechanical office of attach- 
ing the 2ilcint to the soil, and Tceeping it in its proper position. 
The second is the ahsorp>tion of food and moisture from the 
soil. 

THE STEM. 

250. The stem originates in the plumule. The ascending 
of the plumule and descending of the radicle, seem to be 
owing chiefly to the mysterious influence of light. When 
seeds are planted in a box of soil, with a few stalks of hay 
or a little moss spread over it, and then some narrow strips 
of wood placed over all, so that the contents of the box will 
not fall out when it is inverted ; and the box then turned 
with its open side downwards, over a mirror, a bright sur- 
face of tin, or even over white paper, so that the light will 
reach the soil only from below : the seeds will germinate, 
and the plumule descend towards the light, whilst the radicle 
will ascend into the dark soil above it. 

251. Stems are aerial when they grow above the surface 
of the ground, and suhterranean when they grow beneath 
the surface. Erect stems continue to grow in a vertical 
direction. Creeping and trailing stems are such as grow 
along the surface of the ground. Many of these have 
tendrils (coiling fibres) by which they sustain themselves 
on the branches of other plants; as we see in the grape- 
vine. 

252. Subterranean stems generally grow just below the 
surface of the soil. They ai'e distinguished from roots in 
having buds, from which aerial or other subterranean branches 
may be sent forth. The roots of many plants have the power 
of developing buds, and thus sending up " shoots" from their 



154 THE STEM. 

surfiicc ; but still buds are the chief mark of distinction be- 
tween roots and stems. 

253. Forms. — Some of the most general forms of sub- 
terranean roots are : (1) The tuber, a familiar example of 
which wc have in the potato. Its buds (eyes) arc the germs 
of new stems, to be developed the next year. (2) The bulb, 
which consists of concentric layers surrounding one or more 
germs or buds, from which stems spring up, developing new 
bulbs at their base during the succeeding season of growth. 
Examples — the tulip and onion. 

254. Stems are further distinguished by the terms ligneous 
and licrhaceous. A ligneous stem is one which has a woody 
structure, such as wc see in ordinary trees and shrubs; and 
is composed of pith, loood, and hark. An herbaceous stem 
is composed of tissues similar to those of the ligneous stem 
(the cellular predominating), but less compact, softer, usually 
of a single year's growth, and without the distinctions of 
pith, wood, and bark. Ligneous stems are usually distin- 
guished, in temperate climates, by concentric layers of wood, 
marking the annual growth, and thus enabling us to deter- 
mine the age of the tree. Plerbaceous stems usually grow 
but one season : in many cases coming to maturity and dying 
with the ripening of the seed. 

255. Physical Structure of Exooens. — The exogens 
(outside growers), when they first spring from the seed (and 
abo branches, during their first year's growth), have a soft, 
spongy centre of cellular tissue, called pith. This is covered 
by a thin layer of vascular tissue, having its spiral vessels 
connected with the leaves, and called the medullar^/ sheath. 
Surrounding this is the bar/i: Such is the structure of the 
infant plant; but this condition lasts but a short time. The 
sap, carried up by the pith, and elaborated in the leaves, 
descends through the vessels of the liber, and soon forms a 
layer of wood around the medullary sheath. This layer 



THE S T E M. 



155 



Fig. 33. 




consists, first, of ducts or sap-tubes, formed during the early 
part of the season ; then of a more compact kyer of woody 
and vasiform tissue. Such a layer 
is added every year, giving to a 
cross-section of oak or ash an ap- 
pearance similar to that represented 
in Fig. .3.3. 

2.5G. The pith soon ceases to be 
the channel through which the sap 
ascends — the newly-formed ducts 
performing this office. Again the 
laj'ers of wood become gradually 
hard, the sap-tubes partially obstructed by the deposition of 
matter, which gives a reddish or brown color to the wood, 
and the sap ceases to ascend through them. They then form 
the red-wood, called the duramen, on account of its compact- 
ness and strength. For several years the newly-formed layers 
continue to circulate the sap, and retain their light color : 
they form the cdburuum (white-wood — sap-wood_). The 
duramen is the most valuable portion of the tree, on account 
of its strength and durability. The aThurnum is softer, and 
decays readily, on account of the albuminous matter present 
in it (see § IGO), 

257. Passing from the centre of the trunk or stem to the 
bark, and cutting the annual layers at right angles, are many 
plates formed of fine fibres. These are called the medidlary 
rays. They are conspicuous in a piece of split wood of oak 
or maple. 

258. Physical Structure op Endogens. — "In the 
endogenous stem, there is no distinction of pith, wood, and 
bark; nor does a cross-section exhibit any concentric ar- 
rangement of annual layers. It is composed of the same 
tissues and vessels as that of the exogen ; that is, of cellular 
tissue, woody fibre, spiral vessels, and ducts — the first exist- 



153 T II E L E A P. 

ing equally in all parts of the stem, and the rest imbedded 
in it in the form of bundles. Each bundle consists of one 
or more ducts, with spiral vessels adjoining their {yiner side 
next the centre of the stem, and woody fibres on their outer 
side, as in the exogens." — Wood's Botany. 

Most of the endogenous herbaceous stems are hollow, and 
have hard joints at nearly regular intervals. A bladed leaf 
is usually attached at each one of these joints. The joints 
give strength to the stem. Examples are seen in many of 
the grasses. Some stalks, like those of the Indian corn, are 
jointed, but not hollow. 

259. Functions of the Stem. — These are, Jirst, to convey 
the sap from the roots to the leaves, where it is prepared for 
the nutrition of the plant, and thence to carry it to the 
various parts to be nourished by it; secondly, to sustain the 
leaves, flowers, and fruit, so as to expose them properly to 
the action of air and light. Where it is necessary that a 
very large surfoce of leaf should be exposed, the plant is 
constructed with numerous branches, forming a spreading 
top, such as we see on trees generally. In a tree, that part 
of the stem below the branches is called the trunk. The 
trunk is the most valuable part of those trees used for 
timber. 

THE LEAF. 

260. Buds. — Tlants have two kinds of buds: (1) The 
Icaf-huds, the first of which is the plumule as it bursts from 
the seed. This is developed into the stalk and leaves, and 
is itself perpetually renewed on the summit of the stalk. 
Just above the base of each leaf, a new bud makes its ap- 
pearance J and in ligneous plants it is subsequently devel- 
oped into leaves alone, or into a branch and leaves. (2) The 
flower-bud, which has a difi'erent structure, generally having 
enveloped within it the germs of both leaves and flowers. 

In cold climates, buds are protected in winter by a scaly 



THE LEAF. 157 

covering, wliicli opens and frequently drops off soon after 
the bud begins to swell and grow in the Spring. 

261. The leaf combines, in a striking manner, the useful 
and beautiful, in its structure and color. The almost count- 
less shapes, from the straight and slender blade of grass to 
the deeply lobed oak leaf and the broad palm, present to the 
eye a wonderful variety of Nature's most delicate handiwork. 
The green color, the most pleasant to the eye, seems to have 
been provided by a kind Providence to soften the bright 
glare of the summer's sun, and thus to promote the comfort 
of his creatures. 

To the plant itself the leaf bears the most important rela- 
tion. It is the hreatliing organ of the plant — its lungs. It 
is the digestive organ, too — its stomach. 

262. Structure. — The leaf consists of several parts 
worthy of distinct notice. The leaf-stem, or that by which 
it is attached to the branch or stalk to which it belongs, is 
called the '■'■Petiole!^ Some leaves have no petiole, but are 
connected by their base directly with the branch or stem. 
They are then said to be Sessile. The broad expansion of 
the leaf is called the " blade." The framework consists of 
numerous veins and veinlets. The mid-vein is the extension 
of the petiole, running through the centre of the leaf. The 
other veins either branch off from the base of the mid-vein, 
or run parallel with it. The branches of the veins are called 
veinlets. 

263. A leaf is said to be (1) " JVet-veined," when the vein- 
lets so intersect and cross one another as to form a sort of 
net-work. The leaves of exogens, such as our forest trees, 
peas, beans, etc., are net-veined; (2) ^' Parallel' veined," 
when the veins run parallel with the mid-vein, and the vein- 
lets parallel with one another, as in grasses, and most of the 
endogens; (3) " Porlc-veined," when the veins and veinlets 
Vixc forked, as in the fern leaf. 

14 



158 THE LEAP. 

264. Forms. — The form of the leaf is determined by the 
direction and extent of the veins and veinlets, and the deve- 
lopment of the intervening tissue. It may be orhicular, 
round; ovate, egg-shaped; cordate, heart-shaped; lanceolate, 
lance-shaped, etc., according as the outline of the framework 
assumes one or other of these imitative forms. 

265. Physiology of the Leaf. — The veins and veinlets 
may be regarded as a prolongation of the medullary sheath, 
and are composed of the woody and vascular tissues. The 
thin, membranous part of the leaf, or lamina, is formed of 
cellular tissue, and generally consists of two layers; that 
which forms the upper side of the leaf differing somewhat 
in structure from that which forms the lower side. In some 
cases, the plane of the leaf is nearly or quite vertical when 
in its natural position. In such cases, both sides being 
equally exposed to light, have the same structure. 

266. The cells, which abound in the lamina, have their 
inner surface lined with little green globules of chlorophyll 
(§ 179), which give the green color to the leaf. The differ- 
ent shades of green are produced by the greater or less com- 
pactness of the cellular tissue, and consequent compactness 
of the chlorophyll (leaf-green). 

267. Every part of the leaf is enveloped in the epidermii 
(§ 242). Beneath the epidermis, and among the cells, we 
find many open spaces, especially near the lower surface of 
the leaf. These are called air-cham- pm. 34, 

hers, and have communication with the 

air through openings (stomata) in the 

epidermis, which are too small to be 

seen with the naked eye, but with the 

aid of a powerful microscope, they may 

be seen in great numbers. Fig. 34 

represents a magnified view of some of the stomata, as seen 

in the leaf of the lily. They are so numerous on most leaves, 




FUNCTIONS OF THE LEAF. 159 

that many thousands of them are embraced within the space 
of a single square inch of surface. The stomata are chiefly 
confined to the lower surface of the leaf; but in leaves 
whose natural position is vertical, exposing each side alike to 
the sun, they are found on both sides. 

FUNCTIONS OP THE LEAF. 

268. When the sap ascends from the root to the leaf, it 
carries with it in solution a portion of the material necessary 
for the nourishment of the growing plant. But this nourish- 
ment is still in a crude form, and too dilute to be adapted to 
the purposes for which it is designed. It must, therefore, 
undergo certain modifications. These take place chiefly in 
the leaves, as described in the next three sections. 

269. Exhalation. — The sap must be condensed ; that is, 
the surplus moisture must be thrown ofi". This takes place 
through the stomata, and is similar to the perspiration of 
animals. It is generally called ^' exliajation" and occurs 
chiefly under the influence of light, and to a great extent 
independent of temperature. The stomata are open in the 
light, and closed in the darh ; but the direct rays of the sun 
are unfavorable to their action. 

270. Respiration. — Plants derive a large proportion of 
their nourishment from the air, through their leaves, in the 
form of carbonic acid gas. They also absorb small quanti- 
ties of oxygen from the air, but throw ofi" a much larger 
quantity into the air. This inhalation of carbonic gas, and 
exhalation of oxygen, we shall call ^'respiration." In one 
respect it is the reverse of respiration in animals, inasmuch 
as animals inhale oxygen and exhale carbonic gas (§ 65). 
The respiration of plants goes on chiefly by day, the stomata 
being opened under the influence of light. As the carbonic 
gas enters the leaf, it is at once dissolved by the sap, and 
carried through the circulating vessels of the leaf, where it 



160 FLOWERS AND FRUIT. 

is decomposed, its carbon being retained, and its oxygen 
thrown back into the air. 

271. Digestion. — The food taken up by the roots, and car- 
ried by the sap to the leaves, there meets with the gaseous 
food from the air, all together forming, by their solution, 
" crude sap." This is greatly modified during its circulation 
through the leaf, if an abundant supply of light be present. 
The changes which the plant-food thus undergoes, we call 
" digestion," because of its resemblance to the changes pro- 
duced on animal food by animal digestion. When the sap 
has thus been prepared for nourishing the plant, it is called 
" latex" or true sap. It is then conveyed by the circulating 
organs to the various portions of the plant, and in some 
mysterious way, under the guiding finger of Omnipotence, 
assumes various forms of organic structure, producing stems 
and leaves, flowers and fruits. Here we have a beautiful 
analogy between the circulation of sap in plants, and the 
circulation of blood in animals (§ 612). 



FLOWERS AND FRUIT. 

272. Growth, decay, and death, mark the history of every 
individual upon our globe, whether plant or animal. If, 
then, organized beings possessed not the power of reproduc- 
tion, our world would soon become a bleak and barren waste. 
But the Creator has wisely ordained that the earth shall 
bring forth '* grass, and herb yielding seed after his kind, 
and the tree yielding fruit, whose seed was in itself, after 
his kind." 

273. Rrjyrodiictive onjans. — The reproductive organs of 
plant^s are found in the flower, which is the expansion of the 
floicer-hud (§ 260). These, by their combined influence, 
bring the seed to maturity, and thus produce the embryo of 
a new plant. 



FLOWERS AND FRUIT. 



161 



274. Structure of the Flower. — As a general rule, flowers 
have sevei'al distinct organs or parts worthy of note : 

(1.) Many flowers are attached to the plant by a stem, 
called the ''flower-stalk" (Fig. 35, a). When the flower 
rests upon the stem, or branch of the plant, without a flower- 
stalk, it is said to be *' sessile." 



Fig. 35. 




Stamen 



(2.) The head or top of the flower-stalk on which the other 
organs rest, and to which they are usually attached, is called 
the "receptacle" (6). 

(3.) The "calyx" is the external c^/p which surrounds 
the flower at its base. It is generally green, but sometimes 
colored like the other parts of the flower. It is sometimes 
in one entire piece, having its edge notched. At other times 
it consists of a whorl of separate leaves. These divisions of 
the calyx are called "sepals" (c). 

(4.) The delicate and beautifully colored circle of leaves, 
forming the inner coating of the flower, is the " corolla." Its 
divisions are called "petals" (d^. 

(5.) The "stamens" are the slender organs of thread-like 
14* 



1G2 



FLOWERS AND TRUIT. 



structure, situated within the corolla, and generally (though 
not always,) equal to the petals in number (e). 

The three divisions of a stamen are : the filament, or 
slender stem ; the anther, which is a little two-lohed organ 
at the extremity of the filament; and the pollen, or fine yellow 
dust found in the anther. The pollen, when viewed with a 
microscope, is found to consist of minute membranous sacks 
filled with a fluid substance (Fig. 35,/, (7, /i). 

(6.) Within the circle of stamens are the "pistils." These 
occupy the centre of the flower. Some flowers have but one 
pistil, others have a great many (Fig. 35^ i). 

2,1b. The pistil has three divisions : the ovary, which is 
the enlarged part of the pistil at its base, and contains the 
germs of the future seeds j the style, the slender part of the 
pistil rising above the ovary; the stigma is the top of the 
pistil, and usually consists of one or more rounded lobes. 

The ovary is often simple, consist- 
ing of a single cell, or carpel; but 
more frequently it is compound, having 
two or more carpels. When the ovary 
is simple, it has but one style and 
stigma ; when compound, it has a style 
and stigma for each carpel; unless the 
style is wanting, as sometimes happens. 
In that case, the stigma rests upon 
the ovary, and has one division for 
each carpel. (Fig- 36, a, shows a 
simple pistil with its diff"erent parts; h, one of compound 
form.) 

276. Stamens and p>ist!ls are essential organs for the pro- 
duction of seed in any plant. But they are not always found 
in the same flower. (1.) They often grmo in different fiowers 
vpon the same stalk. In such cases, the flowers containing 
the stamens arc called " staminate," and those containing the 



Fig. 36. 




FUNCTIONS OP THE FLOWER. 1G3 

pistils are called " pistilate." For example, Indian corn lias 
its stamens in the tassel, and its pistils in the ear-shoot. The 
tassel then is the staminate flower, while the shoot, with its 
silk, forms the pistilate flower; the tassel, with its beauti- 
ful, pendulous stamens, and the shoot with its fine glossy 
silk, present interesting objects of study. (2.) The staminate 
and •pistilate floxoers sometimes grow on sejjarate plants. Of 
this, we have an example in common hemp>. A little exami- 
nation will enable the student to distinguish between the 
staminate and pistilate plant. The staminate is barren — 
the pistilate produces seed. 

FUNCTIONS OF THE FLOWER 

277. The corolla is the breathing organ of the flower; 
but, unlike the leaf, it absorbs large quantities of oxygen, 
and exhales corresponding quantities of carbonic gas. The 
same process is carried on to some extent by the stamens 
and pistils. 

278. The end to be accomplished by the stamens and 
pistils, is to fertilize the seed. Pollen is produced in the 
anthers ; and by them is so discharged at the proper season, 
that portions of it fall upon the stigma. The little granules 
of pollen then burst, and their contents are absorbed by the 
stigma, and carried through the style to the ovary, where 
they take part in the formation of the seed. If the pollen 
is cut oft' from the stigma entirely (as may be done in an 
isolated stalk of corn, by destroying the tassel before the 
silk makes its appearance), no seed can be produced. But 
if other tassels are near at hand to provide pollen, the stalk 
may produce an ear without a tassel of its own. 

There are certain periods in the growth of crops, when 
the pollen, and even the stamens, may be beaten ofi" by vio- 
lent rains and hail, to such an extent as greatly to diminish 



104 FUNCTIONS OP THE FLOWER. 

the quantity of grain which would otherwise have been 
produced.* 

279. By a wise provision of the Creator, the flower is so 
constructed that the pollen is readily transferred from the 
anther to the stigma. When the flower grows erect, like the 
tulip, the pistil is shorter than the stamen ; and the anther 
rising above the stigma, readily discharges its pollen where 
it is wanted. So, when the flower droops, as the lily, the 
pistil is longer than the stamen, in order that the pollen may 
still fall upon the stigma, (see Fig. 35). 

When the staminate and pistilate flowers are on difier- 
ent plants, the pollen is sometimes carried from the one 
to the other by the wind; sometimes by bees, and other 
insects. 

280. Fruit. — When the ovary is fully developed, it forms 
the fruit. The fruit consists of two parts : (1) The 2)crir 
carp, which surrounds the seeds ; and, (2) The seeds, which 
contain the germs of new plants. 

In the apple, peach, etc. the pericarp is the most valuable 
portion of the fruit. In cereal or grain crops, the seed is 
of chief value — the pericarp being the chafi" or husk. 

281. The seed may be divided into: (1) The integuments 
(bran), which consist of several layers, forming the outer 
coating of the grain ; (2) The albumen, which is the white, 
starchy mass within the integuments ; and, (3) The emhryo, 
or germ of the new plant, which is also within the integu- 
ments, and generally surrounded in part by the albumen. 

The albumen constitutes the larger part of cereal grains, 
and serves not only as food for the embryo plant, but also 
constitutes a large proportion of the food of man and beast. 

* The wheat crops, in the summer of 1858, were seriously damaged, 
in some places, by the heavy rains which fell while the grain-fielda 
were in full bloom. 



QUESTIONS. 165 

DURATION OF PLANTS AND THEIR ORGANS. 

282. When a root or stem lives through only one summer, 
it is said to be annual. When it lives through hco, it is 
said to be biennial; and when it lives through three or more, 
it is said to be perennial. 

(1) The root and stem are often hoth annual, as in flax, 
hemp, Indian corn, cotton, and tobacco. (2) The root may 
be biennial, and the stem annual. In such cases the stem 
does not usually make its appearance until the second season. 
Examples — the common thistle and winter wheat. (3) The 
root may he perennial, and the stem, annual, as in most varie- 
ties of grass. (4) Both root and stem may be perennial, as 
we see in trees and shrubs. 

283. Leaves are deciduous when they die and fall at the 
close of summer, or as soon as the plant has reached matu- 
rity. They are evergreen, when they endure until the new 
leaves of the next growth have made their appearance. It 
is, properly speaking, the plant, and not the leaf, which is 
evergreen ; for the old leaves of evergreen plants, like the 
pine, drop off in the spring, as the new leaves come out to 
take their place ; and thus the succession of leaves keeps the 
plant ever green. 

Climate modifies the duration of the leaf. A plant may 
be ever green in a warm climate, while its leaves become 
deciduous when removed to a colder region. 



QUESTIONS ON CHAPTER XI. 

I 241, 242, 243. What are the chief organs of a plant ? What is 
the bark ? Its divisions ? Describe each. Of what kinds of tissue 
composed? What are stomala? What are glands? Their office? 
Hairs, stings, and prickles ? 

244, 245, 240, 247, 248, 249. Purposes served by the roots? Va- 
rieties of form? Describe the branching root. Spindle root? Tur- 
nip root? Tubei'ose root ? Fibrous root? Aquatic roots ? Aerial 



166 QUESTIONS. 

roots ? How do they grow ? When called brace roots ? The caudex 
of a root ? The fibrihs ? The spongioles ? What does the root re- 
semble in structure? How does it differ from the stem? The two 
principal functions of the root? 

250, 251, 252, 253, 254. Where does the stem originate ? Influence 
of light? How illustrated ? Aerial stems? Subterranean stems? 
Creeping stems ? What are tendrils ? Where do subterranean stems 
generally grow ? What are tubers ? Examples ? Bulbs ? Exam- 
ples ? What is a ligneous stem ? Herbaceous stem ? 

255, 256, 257. Describe the structure of exogeus ? How do they 
grow ? Changes in the layers of wood ? Duramen ? Alburnum ? 
Medullary rays ? 

258, 259. Give the structure of endogens. What kind of stems 
have they? What form of leaf? Use of joints? First function of 
the stem ? second ? Use of branches ? 

200, 261, 262, 263, 264. What does the leaf combine? Variety 
of forms? Its color? Its use to the plant? How many kinds of 
bud? Describe each. How protected in warm climates? What is 
the petiole of a leaf? Blade? Describe the frame-work. When is 
a leaf net-veined ? Parallel-veined? Fork-veined? What are some 
of the forms of leaves? 

265, 266, 267. How may the veins and veinlets be regarded? 
Describe the lamina. How do the two sides of a leaf generally 
differ ? Where is the chlorophyll found ? In what is the whole leaf 
enveloped? Describe the air-chambers. The stomata. 

268, 269, 270, 271. What does the sap carry up from the roots? 
How is the sap condensed ? When are the stomata open, and wheu 
closed ? What do plants absorb from the air by their leaves ? Do- 
scribe the process of respiration. How is sap modified in the leaf? 
What is it then called ? How does it promote growth ? Analogy ? 

272, 273. If organized bodies had not the power of reproduction, 
what would be the consequence ? Where are the reproductive organs 
found ? What is the flower ? 

274, 275, 276. What is the flower-stalk? When is a flower "ses- 
sile " ? What is the receptacle ? The calyx ? Sepals ? Corolla and 
petals? Stamens? Its parts ? Pistil and its parts ? Simple and 
compound ovary? Describe Figs. 35 and 36. What organs are 
essential to the production of seed ? Are they always in the same 
flower? Example? Are they always on the same plant? Example? 



QUESTIONS 107 

277, 278, 279. Hotv is the respiration of the flower carried on? 
Functions of the stamens and pistils ? How is the seed fertilized ? 
What if the pollen is cut off from the pistil ? Illustrate. Effects 
of violent storms ? What provisions are made to secure the transfer 
of pollen to the stigma ? What if the pistilate and staminate flowers 
are on different plants ? 

280, 281. What is the fruit? Its parts? What is the valuable 
part of apples, peaches, etc. ? Of cereal grains ? Divisions of the 
seed ? 

282, 283. What is an annual root or stem ? A biennial ? Are the 
root and stem ever both annual ? Examples ? Can a root be bien- 
nial and a stem annual? Examples? INIay the root be perennial 
and the stem annual ? Examples? May both be perennial ? Exam- 
ples ? When are leaves deciduous ? When is a plant evergreen ? 
Influence of climate ? 



168 AGRICULTURAL GEOLOGY. 



CHAPTER XII. 

THE SOIL. 

284. Having before us the composition of the plant and 
its organic structure, we may now study more minutely its 
nutrition and cultivation. We have given some attention to 
the sources from which crops get their nourishment. These 
are the atmosphere and the soil. We can exercise no con- 
trol over the condition of the air. Our Creator has esta- 
blished laws by which its chemical composition is made 
almost invariable. The quantity of moisture, too, which it 
brings and pours out as rain upon our farms^ is a matter en- 
tirely beyond our influence. 

The management of the soil alone has been committed to 
our hands. Then, leaving the atmosphere in the hands of 
that all-wise and beneficent Being who has made it an inex- 
haustible source of food for plants, and of fertility to the 
soil, let us turn our attention to those principles and laws 
which will guide us to a knowledge of the origin and nature 
of different soils, and to the means by which they can be 
best cultivated and improved 

AGRICULTURAL GEOLOGY. 

285. "Geolo<ji/ is the history of the mineral masses that 
compose the earth, and of the organic remains which they 
contain." — Hitchcock. 

286. In its relations to agriculture, geology points us to 
the origin of soils, and the influence which the rocks have 
had in determining the physical and chemical characters of 
different soils. They have their origin, generally, in those 



AGRICULTURAL GEOLOGY. 109 

masses of mineral matter upon wliich they rest. On the 
mineral character of difiereut rocks, then, the mineral char- 
acter of soils must, to a great extent, depend. Alluvial and 
drift soils are exceptions. 

287. The term "rock" embraces all the solid mineral 
matter of our globe ; that is, not simply the firm, unyielding 
masses, ordinarily called rocks, but also deposits of clay, and 
other loose material, which may not be very coherent in its 
character. 

288. When we examine the rocks of the earth we find 
them under two general forms. (1.) Some of them are in 
layers, which are nearly parallel, and lying one above an- 
other. Each one of such layers is called a "stratum;"* 
and masses of rock of this structure are said to be "stratified." 

Fig. 37. 



Fig. 37 represents a section cut through stratified rocks. 
The strata are sometimes horizontal, as at c, c. At other 
times we find them inclined, as at 1, 2, 3, 4. They are then 
said to have a dq:). The angle, which the face of the stratum 
makes with the horizon, measures the dip. But few of the 
stratified rocks are entirely horizontal, most of them having 
a greater or less dip. 

289. (2.) The other general form under which rocks are 
found, is that of large, irregular masses, having no regular 
layers ; these are termed unstratified. The unstratified rocks 
seem generally to have been thrust up through the stratified, 
and often form the central part and tops of long ranges of 

* Plural, <' strata." 
15 



170 



A G U I C U L T U II A L O E L O O Y. 



hills or mountains. The rocks at a, a, Fig. 38, are unstra- 
tified^ and form the central part, or axis, of the mountain ; 



Fig. 38, 




while those at b, h, are stratified, and seem to have been 
elevated from their original position by the upward force of 
the central mass, a, a. 

290. Stratified rocks generally bear marks of having been 
deposited by water, just as we find them undergoing forma- 
tion now. Such being the case, they must have been origi- 
nally formed in a horizontal position, or nearly so. 

The unstratified rocks bear evidence of having been sub- 
jected to great heat, and seem often to have been thrown 
up from beneath the earth's surface in a melted state. 
Hence, they are frequently called " igneous rocks." 

All the rocks, whether stratified or unstratified, are com- 
posed chiefly of a few minerals. 

291. A MINERAL is any substance icliich is not the result 
of animal or vegetable growth. 

All objects which we can perceive by our senses, have 
been assigned to some one of what are called the three great 
kingdoms of nature : the animal, vegetable, and mineral. 
Every object, then, upon the earth, which has not resulted 
from the action of vitality ^ must be mineral in its character. 

292. Let us examine some of the simple minerals which 



AGRICULTURAL GEOLOGY. 



171 



enter most largely into the composition of rocks and soils, 
These are Quartz, Talc, Clay, Feldspar, Mica, Hornblende, 
and Limestone. 

293. a. Quartz. — The purest specimens of quartz are 
found in crystals of the forms seen in Fig. 39. The crystals 



Fig. 39. 




ft^ 



U. 



are six-sided prisms, terminated by six-sided pyramids. The 
different faces of the crystals often vary very much in size, 
as those at a and b. The sharp angles of this mineral scratch 
glass very readily. It is the same mineral which we find in 
the form of flint, sand, carnelian, agate, &c. When particles 
of sand are cemented into masses, they form sandstone, one 
of the most common forms of quartz. 

294. Chemical relations. — We have already learned (§ 84,) 
that quartz (or silica) is an acid in its chemical relations, 
and has the symbol SiOsj its proper chemical name being 
silicic acid. At a very high temperature, silica combines 
readily with strong bases, such as soda, potassa, and lime, 
forming silicates. Natural silicates are very numerous, as 
we shall presently see. 

295. I). Talc is a silicate of magnesia. It is sometimes 
found in layers as thin as paper, and of a green, or greenish- 
white color. The surface, when rubbed with the fingers, 
feels greasy. When a layer of it is bent, it does not regain 
its former condition like mica, a mineral of the same form. 
Soapstone and French chalk are compact forms of talc. 



172 AGRICULTURAL GEOLOGY. 

296. c. Clay is a silicate of alumina (Al203,3Si03), and 
is found abundantly all over tlie world in fine grains, which 
form a cohesive mass when wet. Slate is a compact form 
of clay. Mingled with sand, pebbles, and organic matter, 
clay constitutes the body of the great majority of soils. When 
pure, it is white, but we generally find it colored with oxides 
of iron and manganese. Although not a fertilizer, in the 
sense of aiFording nourishment for the plant, it serves an 
important purpose in giving compactness to the soil, and in 
retaining moisture, ammonia, and other fertilizing substances. 

297. d. Feldspar is a double silicate of potassa and alu- 
mina. Soda occasionally takes the place of the potassa in 
whole or in part, and modifies to some extent the character 

of the mineral. When feldspar occurs 
Fig. 40. . , , , , , n 

in regular crystals, they have the lorm 

represented in Fig. 40, called an oblique 
rhombic prism. The crystals are often 
quite Jlaf, and have their ends so modi- 
fied as to appear less regular than the 
figure here given. The surface of a 
crystal has the lustre of glass, with a 
somewhat pearly appearance. White, 
gray, and flesh colors are very common 
in this mineral. It is not quite so hard as quartz, but is suf- 
ficiently hard to scratch glass. 

298. When exposed to the weather this mineral is decom- 
posed. Most of the silicate of potassa is removed, while the 
silicate of alumina remains as a finely-divided clay. This 
clay is called " Kaolin," and is the best material for making 
porcelain ware. — (^Ka)ic.} 

' 299. In the disintegration and decomposition of feldspar, 
we have a striking illustration of the part which carbonic 
acid performs, in connection with other agencies, in pro- 
ducing changes of character in rocks. The silicate of 




AGRICULTURAL OEOLOGY. 173 

potassa is decomposed by the strong affinity between potassa 
and carbonic acid, a carbonate instead of a silicate being 
produced. This carbonate of potassa is readily dissolved 
and carried off by rains, while the silicate of alumina re- 
mains, as a minutely divided clay. But there is always 
enough of potassa (and soda, if it be present) retained to 
meet the wants of the resulting soil. If other minerals, 
such as quartz and mica, are contained in the same rock with 
the feldspar, these generally remain in fragments, mingled 
with the clay. 

Soils formed chiefly from feldspar are usually of a light 
color, becoming darker where any considerable quantity of 
iron is present. And while they abound in potassa and soda, 
they are deficient in lime, magnesia, and some other import- 
ant mineral ingredients. 

300. e. Mica is frequently known as mineral isinglass. 
It occurs in thin transparent leaves, and in shining scales 
mingled with other minerals. When found in masses, it is 
easily split into extremely thin layers. These are much 
more tough and elastic than those of talc. It varies in 
color from very light to quite black shades. Heat of a lamp 
or ordinary fire has but little effect upon it; hence the trans- 
parent varieties are used for making windows in stoves, and 
instead of glass for lanterns. Mica is a double silicate of 
potassa and alumina, but differs in composition from feldspar 
chiefly in having only about half so much potassa ; nor is 
it so readily decomposed as feldspar. 

301. Quartz, feldsjyar, and mica are the constituents of 
granite. They are not chemically combined in the rock, but 
mechanically mingled. Granite is one of the most import- 
ant of the unstratified rocks (§ 289), and is extensively used 
as a building material. Masses of this rock are found at 
many points over the region of country between the Blue 
Ridge and Tide-water. When exposed to air and rain, 

15* 



174 AGRICULTURAL GEOLOGY. 

granitic rocks are gradually broken down into mixed masses 
of clay, sand, and mica. The clay results from the decom- 
position of feldspar, as mentioned (§ 299) above ; while the 
silica and mica are liberated in fragments more or less crys- 
talline — the former constituting fine or coarse sand, or quartz 
pebbles, according to the original texture of the rock; the 
latter generally appearing in small shining scales, varying 
greatly in both size and color. 

Gneiss is another rock having the same mineral ingredients 
as granite, but differing from it entirely in structure. While 
granite belongs to the igneous rocks, gneiss belongs to the 
primary stratified rocks. It has great variety in its struc- 
ture; sometimes existing in thin layers, or lamina?, passing 
gradually into what is called mica-slate; at other times more 
compact and finely granular, and having a less distinct strati- 
fication. The minerals (quartz, feldspar, and mica) composing 
it are always crystalline. This rock abounds in the Piedmont 
country lying along the eastern side of the Blue Ridge, as 
well as in all regions where the primary stratified rocks make 
their appearance. It is often improperly called " granite." 
The soils resulting from its disintegration are similar to those 
from real granite. But difierent specimens of both granite 
and gneiss vary widely in the proportions in which their con- 
stituent minerals occur, and of course must give a correspond- 
ing variation in the soils they produce. 

302. /. Hornblende is composed of silica combined with 
magnesia, lime, oxide of iron, and alumina. The difierent 
varieties, however, vary slightly in composition. Its crystals 
are sometimes short, stout prisms, and at other times are long 
and slender. In fine fibres, easily separated, and very flexi- 
ble, it forms ashestus, a substance used for making incombus- 
tible cloth. 

303. Trap is a hard, unstratified rock, not unfrequently 
called " greenstone." It is an intimate mixture of feldspar 



CRUST OF THE EARTH. 175 

and hornblende. When worn down to the proper condition, 
it makes a fertile soil. The feldspar furnishes an abundant 
supply of potassa, while the hornblende gives lime, magne- 
sia, and oxide of iron. Besides, rocks of this kind, like most 
others, have no inconsiderable traces of phosphates, sulphates, 
and chlorides about them. 

304. Hornblende may take the place of mica in granite. 
The rock is then called " syenite." 

305. g. Carbonate of Lime is found under a great 
variety of forms. Common limestone, marble, and tufa are 
forms of carbonate of lime. It is often seen in white crys- 
talline masses or veins, with common limestone. Again, it 
hangs like beautiful icicles from the roofs of caverns, and 
accumulates in huge porous masses of tufa around limestone 
springs. 

306. By burning any one of these forms of this mineral, 
it is converted into lime. The quality of the lime depends 
upon the purity of the rock from which it is prepared. Car- 
bonate of magnesia, and the silicates of lime and magnesia, 
are very common constituents of limestone rocks. (See sec- 
tions on lime.) 

CRUST OF THE EARTH. 

307. Geologists generally believe that the inner part of 
the earth is a mass of mineral matter in a molten state, as 
we see it issuing from the craters of volcanoes; and that 
only a crust of solid rocks surrounds it on all sides. The 
thickness of this crust is supposed to be less than one-fortieth 
of the distance from the surface to the centre of the globe. 
Some of the rocks of the earth, as heretofore stated, are 
stratified and others unstratified. 

308. The stratified rocks have been formed under water, 
in the bottoms of oceans, seas, and lakes, or at the months 
of rivers. The material of which they are composed, when 



170 CllUST OF THE EARTH. 

deposited by water, would naturally assume a horizontal 
position. By the varying action of freshets, waves, and 
currents, layer upon layer would be built up. Embedded 
in rocks thus formed, we might well expect to find the re- 
mains of plants and animals ; and so we do, in most of them. 
Nearly all of the higher stratified rocks contain shells, the 
bones of fish and land animals, with many varieties of plants, 
^^among which are the leaves, branches, and even trunks of 
trees. These remains of animals and plants thus found in 
the rocks are known as " fossils," and the rocks containing 
them arc said to be fossiUferous. 

The fossils deposited in the rocks are sometimes so abun- 
dant as to constitute the whole mass, except mineral matter 
deposited from water, either in the fossil body itself, or be- 
tween the different fossils, so as to solidify (petrify) them in 
the first instance, and then cement them together. In all 
cases where fossils abound, they have exerted a considerable 
influence on the chemical, as well as the physical, character 
of the rocks in which they occur; and have, consequently, 
taken part in determining the quality of soil formed from 
those rocks. 

By volcanic forces, acting from beneath, the stratified 
rocks have been elevated to various heights, and thrown 
into various positions, and now form a large portion of the 
surface of the continents and islands inhabited by man. 

309. Formations. — The strata of the earth have been 
classified into several distinct formations. Of these we can 
take but a brief general view. Fig. 41* will aid the memory 
in retaining their names and relative position. It is designed 
to represent an ideal section of the earth's crust, made at 
some point where all the formations are found. The reader 
must beware of falling into the mistake of supposing that 
each one of these formations may be found everywhere on 
the earth's surface; or that any one of them ever enveloped 

* See Frontispiece. 



CRUST or THE EARTH. 177 

the whole globe ; or that one of them cannot occur ■without 
being accompanied by the others; or that, when found, they 
uniformly all succeed each other in the order here given. 
By examining the surface of the earth, as represented in the 
figure, it will be seen that one formation alone may give cha- 
racter to the soil and rocks for several miles together, as in 
the space from a to h. Again, the silurian formation, for 
example, may have been deposited over a very wide section 
of ocean-bottom : a part of this may have been subsequently 
elevated, while the old red sandstone was being deposited 
over the remainder; then above this the other formations, 
up to the tertiary, at which period the whole (or perhaps 
some portion of the original sea-bottom on which the sdiirian 
rocks alone had been formed) may have subsided during the 
period when the tertiary were formed ; and thus the tertiary 
might be found to rest upon the surface of the Silurian for- 
mation. Such is the case at c, in the figure. 

310. I. Primari/ Stratified Rochs. — These are lowest in 
the series, and contain no fossils. They consist chiefly of — 
(1) Gneiss, described in §301. (2) Mica-slate, composed 
mostly of quartz and mica, the latter being in such quantity 
and form as to give a slaty structure to the mass. (3) Tal- 
cose-slate, similar to the above, but having talc in the place 
of mica. It often contains some mica and feldspar. The 
surface of this slate generally feels smooth or greasy, but 
not to the same degree as pure talc or soapstone. (4) Horn- 
hlende-slate, in which hornblende predominates. It also con- 
tains portions of quartz, feldspar, and mica in many of its 
specimens. (5) Clay-slate, a finely granular rock, in thin 
layers. Its structure is frequently such, that it can be split 
into tiles for covering houses; and when dressed oflf and 
framed, it forms the "slates" used in schools. (6) Sand- 
stone, of various shades of color. (7) Primary limestone is 
in some places found in strata lying between other primary 



178 CRUST OF THE EARTH. 

strata. Primary stratified rocks are also called "3Ietamor- 
phic Rocks." They are crystalline in their structure. 

311. II. The Silurian Formation lies next above the 
primary. We shall not take any notice of the suhdivisions 
of this, or of any of the following formations. The Silu- 
rian rocks are : (1) Sandstone ; (2) Several varieties of 
slate; (3) Jvi'mestoue in great abundance ; (4) Conglomerates; 
that is, rocks composed of little rounded pebbles and sand 
cemented together. 

Fossil shells and coral abound in this formation. The 
remains of fish and plants, too, are sometimes found in it. 

312. III. The Old Red Sandstone (or Devonian) is 
the third in order, and derives its name from the abundance 
of red sandstone found in it. Its rocks are chiefly sand- 
stones and conglomerates, with some limestones and slates. 

The most remarkable fossils of this formation are its 
peculiar fishes, which are described in recent works on 
geology. 

313. IV. The Carboniferous Formation is chiefly 
distinguished by its immense beds of mineral coal. The 
great quantity of carbon found in it gives it the name by 
which it is known. The coal is found in seams or strata of 
various degrees of thickness, lying among strata of slate and 
sandstone, with an occasional stratum of fossil limestone. 

Besides a great variety and abundance of fossil plants, this 
formation^ontains fishes, shells, insects, etc. 

314. V. The New Red Sandstone forms the boundary 
of the coal formation above, as the old red forms its bound- 
ary below. Sandstones of various colors, magnesian lime- 
stones, slates, etc. make up the rocks of this division. No 
distinction has been made by us between the Upper New- 
red, and the Lower New-red, or Permean system. Bird- 
tracks and fish-bones are abundant here. 

315. VI. The Oolitic and Lias. — "In many of the 



CRUST OF THE EARTH. 1 79 

rocks of this series, small calcareous globules are imbedded, 
which resemble the roe of a fish ; and hence such a rock is 
called roestone, or oolite. But this structure extends through 
only a small part of this formation, and it occurs also in other 
rocks. 

" The oolite series consists of inter-stratified layers of clay, 
sandstone, marl, and limestone. The upper portion, or that 
which is oolite proper, is divided into three systems or groups, 
called the upper, middle, and lower, separated by clay or marl 
deposits. 

" In this country no genuine oolite has been found. But 
the remarkable coal-field in Eastern Virginia, near Richmond, 
is most probably of the age of the oolite and lias^ as has 
been shown by Prof. W. B. Rogers. 

" Lias is a rock usually of a blueish color, like common 
clay ; and it is, indeed, highly argillaceous, but at the same 
time generally calcareous. Bands of true argillaceous lime- 
stone do, indeed, occur in it, as well as of calcareous sand. 
It has been usual to describe it as a member of the oolite 
series. But it is widely diifused, is very marked in its cha- 
racters, and contains peculiar and very interesting organic 
remains." — H'dchcoch. 

Fossil coral and fish are abundant in this formation, but 
its most striking peculiarity consists in the number and im- 
mense size of its re/ptiles. 

316. VII. The Cretaceous Formation takes its name 
from the chalk (crcta) in which it abounds in some countries, 
especially in Europe. In this formation the green sand, so 
successfully employed as a fertilizei: in some parts of our 
country, is found. Green sand is also found in the higher 
strata. 

317. VIII. The Tertiary Formation is the highest 
division of the stratified rocks. The strata in it are gene- 
rally more nearly horizontal than in any of the lower forma- 



180 CRUST OF THE EARTH. 

tions. It is composed of clay, limestone, marl, and sand, 
with occasional beds of gypsum and rock-salt. 

Many of the fossils of this period are the remains of plants 
and animals closely resembling those now living upon the 
earth. But in the rocks of lower ormations, the fossils in- 
dicate that our earth was formerly inhabited by beings dif- 
fering widely from any now known to man. The most re- 
markable feature of the tertiary period, is seen in the number 
and size of its mammalia. 

318. IX. Alluvium and Drift. — Above all the stratified 
rocks we discover, everywhere, quantities of loose material, 
broken down and worn off from rocks of every kind, and 
scattered over the surface. When this material is carried 
by water, and deposited along the valleys and in the bottoms 
of ponds and lakes, it forms v^hat is called ''Alluvium," and 
soils thus formed are alluvial. The material of which they 
are composed, is generally collected from a considerable va- 
riety of rocks, and hence they have all the mineral elementa 
necessary to render them fertile. 

In many places vast currents of water, accompanied most 
probably by masses of ice, have swept over extensive regions, 
carrying with them the abraded material from the various 
rocks, and hills, and mountains over which they have passed, 
and again depositing it, as a mixed mass of sand and clay, 
full of pebbles and boulders of almost every conceivable size 
and shape. This constitutes the " Drift formation." 

The Drift forms a very important feature in the geology 
of some of our Eastern States, and also at many points in 
the Northern and North-western States ; but it rarely occurs 
farther south than the Ohio River, except as local drift. It 
differs, of course, from the rocks beneath ; and frequently 
gives a fertile soil, immediately over rocks which would have 
produced only a barren desert. 

319. X. Beneath the stratified rocks, in many places rising 



CRUST OP THE EARTH. 181 

up through and often over-lying them, we find the iinsirati- 
ficd rocks. These bear no marks of having been deposited 
by water, but seem to be of volcanic origin. 

The most prominent minerals which enter into the com- 
position of these rocks are Feldspar, Hornblende, Quartz, 
and Mica. These combining, give us Trap rocks. Granite 
(including Syenite), and many less abundant varieties, of 
"which we have not room to give a description. 

320. Whenever the rocks, whether stratified or unstrati- 
fied, are long exposed to the influence of air, rain, and frost, 
or even of air and rain alone, they are gradually broken 
down, as heretofore stated, into small fragments. These 
undergo many subdivisions, until the little separated particles 
of sand and clay, mingled with such organic matter as pre- 
viously existed in the rock, or has meanwhile been growing 
among the fragments of its half-formed soil, become one 
mixed mass, and at the same time pass through such chemi- 
cal changes as adapt them to the great end for which they 
were designed. 

321. The original quality of the soil must, then, be greatly 
dependent upon the character of the rocks out of which it has 
been formed. Yet it is not difference in the mineral compo- 
sition of rocks alone, that causes differences in the nature of 
soils ; the organic, fossil matter, deposited when the rocks 
were formed, seems often to have had a most striking in- 
fluence. Any one may observe for himself, in traversing 
a hilly or mountainous region, how suddenly he sometimes 
passes from one quality of soil to another, even in the same 
field. And in uncultivated lands, he may frequently meet 
not only with abrupt changes in the rocks and soil, but 
changes just as abrupt in the trees, shrubs, and weeds, which 
nature seems to have adapted to the varying quality of their 
mineral food. 

322. Pure granitic soils contain the disintegrated particles 
16 



182 CRUST OF THE EARTH. 

of quartz, feldspar, and mica, from the granite rock. The 
feldspar is soon decomposed, by the action of carbonic acid, 
into carbonate of potash and fine clay. The little crystals of 
quartz are but slightly modified, forming, -when set free, sand 
of various degrees of fineness. From hilly lands the fine 
clay is gradually carried down into the low grounds, and a 
covering of sand, generally with clay beneath it, is left to 
form the poor, barren soils of the surrounding hills. But 
even where all the material of the granite is retained, the 
soil is generally deficient in li7ne, magnesia, and oxide of 
iron. 

When granite contains liornhJende, as it often does, this 
furnishes lime, magnesia, andi iron, and such a soil is gene- 
rally productive. Or, if granite and trap rocks occur on the 
same hill, the soils from both may become mingled by the 
action of rain and frost, or by tillage, and thus form a better 
soil than either would form alone. 

323. Traj) rocks, being composed, as we have learned, of 
feldspar and hornblende, are acted upon by air and water, 
both mechanically and chemically. The result is a finely 
divided soil, to which the feldspar furnishes an abundance 
of clay and potassa, with some soda; while the hornblende 
yields lime, magnesia, and oxide of iron abundantly; hence 
such soils are generally ftrtile. Some of the best soils of 
Eastern Virginia are formed from Trap. 

324. The primary stratified rocks difi'er widely in compo- 
sition, and, as a consequence, give a great variety of soil. 
We have a most extensive illustration of this in the greater 
part of the wide area, extending from the eastern side of the 
Blue Ridge, on the one hand, to the slope over which the 
rivers flowing into the Atlantic fall, before they reach tide- 
water, on the other ; then, extending northward, it becomes 
narrower as it passes into Maryland, and extending south- 
ward into North and South Carolina, it spreads out to a still 



CRUST OF THE EARTH. 183 

greater width than it has in Virginia. In this region there 
are some behs of fine soil, formed from rocks composed 
largely of feldspar and hornblende. There are other sec- 
tions, in which the soils are composed of the ruins of gneiss 
and granite. These soils are sandy, and less valuable. 
Again, there arc localities in which the soil has originated 
from rocks composed chiefly of quartz, with small quantities 
of mica or feldspar, or both. Such regions are hopelessly 
deficient in the most impoi'tant elements of mineral fertility. 
325. The Great Valley of Virginia is an example of the 
Silurian formation. The western slope of the Blue Ridge 
belongs to this. The rocks here, and on the spurs, which 
often extend out some distance into the valley, are chiefly 
slate and hard sandstone. These form light, unproductive 
soils ; and where the rocks are hard sandstones, they disin- 
tegrate very slowly, break off in large fragments under the 
influence of frost, and form rough, unmanageable soils. As 
we descend into the open valley, we find the formation con- 
sisting of a great variety of limestones, with vast beds of 
interstratified slates and shales,* all containing fossil shells 
and coral. By their disintegration, these rocks generally 
give soils of fine quality. In most parts of this valley, the 
rocks have been very much tilted and warped at the time of 
their upheaval, thus giving rise to a peculiar and interesting- 
variety of landscape. In many places we meet with abrupt 
precipices, such as are common along the banks of water- 
courses ; in other places we find deep gorges, like that 
spanned by the Natural Bridge ; while the less sublime but 
no less beautiful hills, with their gently undulating slopes 
and rounded tops, are found to cover the greater part of the 
surface throughout the whole length and breadth of this 
delightful section of our State. 

* Shale is a brittle, imperfect form of slate. 



184 CRUST OF THE EARTH. 

As century after century has passed away, the solid rocks, 
as Avell as the more brittle shales, have been gradually broken 
down into minute fragments by rain and frost, while the 
carbonic acid brought down by the rain-water has dissolved 
out much of the carbonate of lime, and left the clay to form 
soils varying in depth from less than an inch to many feet. 
The depth of these clay deposits depends partly upon the 
steepness of the land, but still more upon the structure and 
composition of the rock. If the surface is steep, the greater 
part of the liberated clay may have been washed down into 
some neighboring valley, forming there a deep, rich soil, and 
leaving the rocky hill-side almost naked. If the rocks were 
pure carbonate of lime, there could be no residuum of clay 
and sand to produce soil ; but the truth of the case is, that 
nearly all the compact limestones contain a considerable 
amount of these impurities, while some contain not more 
than fifty per cent of carbonate of lime ; and many of the 
beds of calcareous shale have but a small quantity of the 
carbonate, combined with a large quantity of clay. These 
last not only disintegrate more rapidly, but also leave a much 
larger amount of residuary matter than any of the more solid 
rocks. Hence we generally find them underlying deep beds 
of clay. 

The soils resulting from limestone formations are generally 
productive, and remarkably well adapted to the culture of 
grass and grain crops, and also produce good tobacco. Where 
the ancient coral reefs are found among the limestones of 
this formation, the clay which they leave after their decay, 
as well as that formed from the adjacent shales, is rich in 
organic matter, as well as the mineral elements required in 
soils of the best quality. The author has detected ammonia 
in very perceptible quantities, in clay found in a quarry of 
coraline limestone, at a considerable distance beneath the 
surface of the ground. If we suppose this ammonia to have 



CRUST OF THE EARTH. 185 

been produced in the rock by the decay of the coral, by 
■which it wiis built up, and then retained by the clay after 
the rock ha.s been disintegrated, and has had its carbonate of 
lime dissolved out, it affords us a most striking illustration 
of the tenacity with which ammonia is held by clay. [For 
more detailed information, see Prof. Gilham's valuable Essay 
on the Soils of the Valley of Virginia, Journal of State Ag. 
Soc, vol. iii.] 

The mountain ridges lying along the western side of the 
valley, belong also to what we have called the Silurian for- 
mation. Here slate and sandstone prevail. The slate forms 
a soil capable of considerable improvement; but the sand- 
stone is too hard to form a soil suitable for tillage, except 
along the lower slopes of the ridges and in the valleys, where 
the abraded material has been collecting for many centuries. 
When clay from one ridge is carried down by water, and 
mingled with the sand brought down from some neighboring 
ridge, and deposited alor.g the banks of streams,(plants, in- 
sects, fresh-water shells, etc., being mingled with it,)very 
fertile bottom lands are often formed, running in long narrow 
strips through extensive sections of almost barren mountains. 
. — (Rodf/crs.) 

32G. The soils of the Old Red Sandstone are extremely 
variable in our country. Where marl and limestone are 
found in this formation, the soil is generally productive; but 
where the sandstones prevail, as they do extensively in the 
mountainous parts of Western Virginia, lying along the 
eastern side of the coal regions, the soil is generally poor. 

327. In the Carboniferous or coal formation, many of the 
slates and sandstones form soils of no great value ; but belts 
of limestone and calcareous shale sometimes give correspond- 
ing belts of good land. The accumulations of detritus in (he 
valleys, and along the streams, also afford good soils. Where 
the slaty lands of this, or any other formation^ lie in a hori- 
16* 



186 CRUST OF THE EARTH. 

zontal position, they are impervious to water, and hence are 
cold and Tvet. These must generally be drained before they 
can be successfully cultivated (see Chap. XIII). 

What has been said of the influence of the various kinds 
of rock upon the soils overlying the formations already men- 
tioned, will lead us to the general conclusion that the quality 
of the land upon all the higher strata, must be as vari- 
able as the character of the rocks themselves. The sand- 
stones generally give light, infertile soils, while those pro- 
duced from slates and shales are better ; and, when free from 
bituminous matter, and supplied with lime, are often very 
productive. 

328. Some of the formations have the elements of their 
own improvement treasured up within themselves. A striking 
example of this is seen in the marl beds, so abundantly de- 
posited in the tertiary strata lying along our eastern coast. 
Many farms in the tide-water sections of Virginia, Maryland, 
and other States, have been most successfully and profitably 
reclaimed from almost hopeless exhaustion, by the judicious 
application of these tertiary marls. Besides the marl pro- 
per, little mineral nodules of a dark color occur in the 
same beds, or in contiguous deposits; and, on being ana- 
lyzed, they are found to contain a large per cent of pltosphide 
of lime. Prof Johnston, of England, says : '' This crag [a 
tertiary deposit] is chiefly interesting to the agriculturalist 
from its containing hard, rounded, flinty nodules — often 
spoken of as coproUtes — in which as much as 50 per cent of 
phosphate of lime (bone-earth) has been found. These 
nodules are scattered through the body of the marls, and 
through the sub-soils of the fields far inland ; and are col- 
lected for sale to the manufacturers of super-phosphate of 
lime, and other artificial manures." (Aff. Cliem. p. 9J-.) 
Similar black pebbles occur in the Olive Earths and Marls 
of the tertiary strata of Eastern Virginia. Mr. Kufiin, the 



STRUCTURE OF THE SOIL. 187 

venerable and distinguislaed President of the Virginia StJite 
Agricultural Society, first brought these to the notice of 
Prof. Gilham, of the Military Institute, by whom some spe- 
cimens were analyzed. "After being crushed and thoroughly 
mixed, they were found to contain 56 per cent of phosphate 
of lime!" — (Southern Planter, Dec. 1858.) 

329. .The experience of the agricultural world has esta- 
blished a conclusion of great practical importance in the 
selection of lands for tillage. It is this — that, amomj the 
upland soils, none are so uniformly and j^crmanently fertile^ 
as those formied from calcareous rocks. And next to these, 
the soils from the lime-hearing trajj-roclcs occupy the first 
jalace. Alluvial and drift soils, of course, are exceptions. 

STRUCTURE OT THE SOIL. 

330. In examining any soil which has been left undis- 
turbed to pass through its natural stages of formation, we 
find the surface portions differing considerably from those 
nearer the original rocks. They differ not simply in appear- 
ance, but also in composition, and consequently in fertility. 

It is both interesting and instructive to trace out the 
yarious changes which have taken place, in reducing the 
original rocks of the earth to the condition of arable soil. 
Let us take, for example, a calcareous formation, made up of 
limestones and calcareous shales, which have just been up- 
heaved by volcanic agency, and for the first time exposed to 
the disintegrating influence of the weather. The shales are 
rapidly crumbled down to the condition of clay, from which 
the rain gradually dissolves out much of the carbonate of 
lime, carrying it off to foi'm ''limestone springs." The more 
solid rocks are worn down more slowly, but not less surely, 
by the operation of the same causes. In this way a soil is 
gradually formed, supplied with all the mineral ingredients 
of the rocks. But such a .oil, produced by such a process 



188 STRUCTURE OF THE SOIL. 

alone, would still lack one important class of its elements of 
fertility: it would still want the organic matter^wliicli we 
shall hereafter find performing most important offices in the 
production of ])lants. If the rocks have been highly fossil- 
iferous, more or less organic matter may be already present; 
but the supply soon begins to be collected from another 
source. The new soil is gradually provided with the. seeds of 
grasses, herbs, and trees of various kinds, from older lands; 
and such of them as find here their appropriate mineral food, 
soon germinate, take root, and send out their blades and 
leaves to collect carbonic acid from the air (§ 270), while the 
roots themselves drink in the same kind of nourishment from 
rain-water, together with ammonia and mineral matter. Some 
of the roots soon penetrate the lower parts of the soil for 
many feet, whence they draw up mineral substances, and 
send them out iu the saj), to be incorporated with the organic 
food from the air, in the body, and branches, and leaves of 
the growing plant. As the grass, the weeds, and the leaves 
of trees fall and decay upon the surfice, they leave a dark 
rich deposit of humus, to serve as food for the same or other 
kinds of growth. In this way, great quantities of organic 
matter are often accumulated, forming with the clay a deep, 
rich vegetable mould. 

The mineral matter which once fed the decayed leaves 
and grass, has not only been increased in ijuantity near the 
surface, but has also been so elaborated in the plants through 
which it has passed, as to be now in the best possible condi- 
tion to ailbrd nourishment to subseciuent crops growing upon 
the same soil. 

The portion of soil which has thus become enriched with 
organic and mineral substances, is called the "surface-soil," 
and is the part usually cultivated. The " sub-soil " is the 
layer upon which the surface-soil rests. It generally has Init 
little organic matter in it ; and, in the majority of fields in 



STRUCTURE OF THE SOIL. 189 

our Southern and Western States, it has never been dis- 
turbed by the plow. On rolling lands which have been long 
under cultivation, the surface-soil on different parts of the 
same hill is generally more uniform in its character than the 
sub-soil ; because the loose material on the surface becomes 
mingled, by the mechanical action of the plow, rains, and 
frost; while the sub-soil, having been less frequently dis- 
turbed, lies nearer to the rock from which it originated, and 
more nearly resembles it. The value and importance of the 
sub-soil, and its proper management, will be discussed here- 
after. 

331. Classification. — Sand, clay, oxide of iron, car- 
bonate of lime, and organic matter, make up the body of all 
soils. Other ingredients, such as po^assa, soda, phosphates, 
and sidphates, are not less essential to a good soil ; but they 
generally form only a small proportion of the whole mass. 

We may reduce all soils to six genercd classes. And yet 
these divisions will be found to blend into each other, so that 
it will be difficult often to tell where the line of separation 
is to be drawn. Still, a general classification may serve some 
valuable purposes. It may, at least, direct the attention of 
the young farmer to the mechanical differences found among 
different soils, and thus prepare him the better for their me- 
chanical management. The classes we propose are : (1) 
JSandy soils; such as have not less than 75 per cent of sand, 
may be placed under this first class. The quantity of sand 
may be determined with considerable accuracy, by very simple 
means. Uxp. Dry and weigh a pound of soil, and put it into 
a vessel which will hold a gallon or two of water. Pour clean 
water over it, and stir it up thoroughly; then pour the water 
off gradually. The sand will at once subside, on account of 
its weight ; while the particles of clay and organic matter, 
being lighter, will be held longer in suspension by the water. 
By repeating this washing with fresh portions of water, until 



100 STRUCTURE OF THE SOIL. 

the water passes off clear, the sand alone will be left, and 
may be dried and weighed, and the quantity in a pound of 
soil thus determined. (2) A sandij loam is a soil containing 
from 50 to 75 per cent of sand, which may be separated and 
determined by the process above given. (3) A clay loavi 
has only from 25 to 50 per cent of sand, and the remainder 
chiefly dai/. (4) A day soil has less than 25 per cent of 
sand, the remainder being chiefly clay. The dark red clay 
soils have a large per cent of oxide of iron. (5) Any soil 
containing 10 per cent, or more, of carbonate of lime, may 
be called a calcareous soil, whether the remainder be clay or 
sand, or both. Hence, that proportion of calcareous matter 
would exclude a soil from either of the first four classes. To 
determine the quantity of carbonate of lime : heat two 
ounces of icell-dried soil, on a piece of sheet-iron, or in an 
iron ladle, till all the organic matter is burnt out. Then 
pour over it a pint of water, and add a fluid ounce of nm- 
riatic acid. The acid will dissolve all the lime, while it will 
dissolve very little else from the mass. Stir the mixture seve- 
ral times, and let it stand until the remainder of the soil 
settles; then pour off the clear solution. Stir it up with 
another pint of fresh water, let it settle, and again pour off. 
Repeat the same washing with another portion of water. 
Spread the undissolved part of the soil on paper, and dry 
thoroughly. Then weigh again, and the loss of weight will 
be about the quantity of carbonate of lime. This is but a 
rude experiment, and is only applicable where the quantity 
of carbonate of lime is large, and the result aimed at, a mere 
approximation. (6) A peaty soil is one which contains 20 
per cent or more of dark decayed organic matter — such 
soils as are common in low and swampy places. The quan- 
tity may be very nearly determined by burning out the or- 
ganic matter, and ascertaining the loss of weight. 

332. Compactness is a quality of importance in a soil. It 



QUESTIONS. 101 

must be sufSciently firm to hold the roots of the growing 
crop firmly in place. This is especially important in wheat 
and grass crops, which are exposed to the frosts of winter. 
Yet it must not be so compact that the roots cannot readily 
penetrate it. 

The property of absorbing and retaining moisture is im- 
portant. Clay-loam and peaty soils absorb the largest quan- 
tity of moisture, and retain it best ; except those peaty soils 
which have a large excess of organic matter in them. Pure 
clay soils are generally too compact, while sandy soils are 
generally too loose either to absorb or retain moisture well. 
On a level clay soil, the water is apt to become stagnant. 
This is the case, too, on sandy or peaty soils which have 
a clay sub-soil. Under such circumstances, draining is 
required. 

333. Air should be allowed to circulate freely in the soil. 
(1) It carries the elements of plant-food contained in it, to 
the roots. Carbonic gas and ammonia are both furnished, 
and conveyed to the spongioles of the roots in this way. (2) 
It promotes the decay of organic matter present, and thus 
again provides the same articles of food. (3) Moisture is 
often supplied to a dry soil from damp air brought in con- 
tact with it. (4) The proper chemical changes in the mine- 
ral elements of the soil, are promoted by the action of the 
carbonic acid and oxygen of the air. (5) The germination of 
seeds, and growth of the germ, require the circulation of air. 

Let us now turn to the investigation of the principles 
which are to guide us in the mechanical management of 
lands. 



QUESTIONS ON CHAPTER XII. 

I 284. From what sources do plants get their nourishment? Over 
which of these have we any control? 

285— 290. AVhat is GfoZoyy.? Its relations to agriculture? AVhere 



192 QUESTIONS. 

liiive soils their origin'.'' What exceptions? How is the term rock 
u^cd? Wh.at two general forms have rocks? Vl hat \s n stratum? 
I'^xplain Fig. 37. What arc unstratified rocks? How situated? 
Explain Fig. 38. IIow liavo stratified rocks been deposited? Why 
are unstratified called "igneous rocks?" Of v/hat are all rocks 
composed ? 

291, 292. What is ^.mineral? What arc the three great kingdoms 
of nature? What are tiie minerals that enter most largely into the 
composition of rocks and soils ? 

293, 294. Describe (Jua?-^^. When called sandstone? Symbol for 
silica? Why called silicic acid? 

295, 296. What is Talc? Its form? How distinguished from 
mica? What is Clai/? Slate? What gives clay its color? 

297, 298, 299. What is Feldspar? How does it vary in composi- 
tion? Form of its crystals? How are they modified ? Its colors? 
Elfect of exposure to weather? Of what does its disintegration give 
us an illustration ? How does carbonic acid act upon this mineral? 
Quality of soils from feldspar? In what deficient? 

300, 301. In what form does 3Iica occur? Influence of heat upon 
it? Its chemical composition ? Constituents of Granite? Its im- 
portance? What kind of soil does it produce? What is Gneiss? 
Its structure? Where found in abundance ? Its soils? 

302, 303, 304. Composition oi Ilornhlende? Its forms? When 
called Asbestus? What is Trap? What kind of soil does it yield? 
Why? How may hornblende enter into granite? What is it then 
called ? 

305, 306. Forms of Carbonate of Lime? Effect of burning? 
Quality of lime? What other substances are constituents of lime- 
stone? 

307, 308. What do geologists believe concerning the inner part of 
the earth ? IIow have stratified rocks been formed? What are im- 
bedded in these rocks? What are they called ? What of the abun- 
dance of fossils in some rocks? How have the stratified rocks been 
thrown into their present position ? 

309. What docs Fig. 41 represent? Is any one formation found 
everywhere ? Did any one of them ever envelope the whole globe ? 
Illustrate. 

310, 311. Where are the primari/ stratified rocks situated? Of 
what composed? What is the structure of their mineral ingredients? 
What formation next above the primary? Of what composed? 



QUESTIONS. 193 

312. Old Red Sandstone? Its constituents ? Its fossils ? 

313. How is the cfi(7-io?ii/"ero?/s formation distinguished? Its fossils? 
314 — 317. How is the Nciv Red Sandstone situated? Of what 

rocks is it made up ? Point out its position in Fig. 41. How is the 
Oolitic formation characterized? Of what does it consist? What 
coal field has been found in this formation? Describe the Lias. 
What remarkable fossils in the Oolite and Lias? Why is the creta- 
ceous formation so called ? What valuable mineral is found in it in 
this country ? Position of the Tertiary formation ? Trace it out on 
Fig. 41. Of what composed? What of its fossils? 

318. Where are Alluvium and Drift found? What kind of depo- 
sits are called alluvium? Character of its soil ? How has the drift 
formation been produced? What kind of soils does it give? 

319. IIow are the unstratified rocks situated? Their origin? 
Chief minerals? 

320 — 323. Influence of long exposure upon rocks? How do they 
become soil ? What determines the original quality of a soil? In- 
fluence of fossil matter? How does natural vegetation indicate dif- 
ferences of soil? Describe the disintegration of Granite. In what 
are granitic soils deficient? Effect of hornblende on granitic soils? 
What are the constituents of trap rocks? Quality of trap soils? 

324. What kind of soils from primary rocks? What extensive 
region belongs to this formation ? 

325. To what formation does the great valley of Virginia belong? 
Hocks of the western slope and spurs ? Character of their soils ? 
Rocks of the lower part of the valley ? Character of the soils from 
these rocks? The landscape? IIow have the soils been formed? 
Upon what does their depth depend ? Are the rocks here generally 
pure carbonate of lime? The general character of limestone soils? 
How has organic matter been communicated to some of these soils? 
What of the mountain ridges west of the valley? 

326. 327. Old Pied Sandstone soils? Influence of marl and lime- 
stone? Soils of the coal formation? Detritus of the valleys? Why 
are the soils of the higher formations so various? 

328. Example of a formation, having the means of improving its 
soils within itself? What besides marls are found in the tertiary 
deposit ? Example iu England ? Example in Eastern Virginia ? 

329. What general conclusion in regard to soils from calcareous 
rocks ? Class of soils next to these ? 

17 



194 QUESTIONS. 

330. How do the different parts of a soil differ ? First step in the 
formation of a soil? Do the rocks furnish everything necessary to 
fertility? How is a new soil soon provided with plants ? How do 
these increase the quantity of organic matter ? How do they affect 
the quantity and quality of mineral matter? What is the surface 
soil? Sub-soil? Which most nearly resembles the original rocks ? 

331, 332. What minerals make up the main body of all soils? 
What other ingredients must be present ? Can soils be very defi- 
nitely classified? Why not? AVhat are sandy soils? How is the 
quantity of sand determined ? A sandy loam ? A clay loam ? A 
clay soil ? A calcareous soil ? To determine the quantity of carbo- 
nate of lime ? A peaty soil ? Why are such soils common ? Why 
is compactness important in a soil ? For what crops especially ? 
Absorbent power of soils ? Why is draining often necessary ? 

333. What should have free circulation in the soil ? First reason? 
Second? Third? Fourth? Fifth? 



MECHANICAL TREAT 3IE NT OF SOILS. 195 



CHAPTER XIII. 

MECHANICAL TREATMENT OF SOILS, 

334. In reducing soils to tlieir proper mechanical condi- 
tion, three points must be kept distinctly in view: (1) They 
must he sufficientlt/ pulverized to alloxo the roots of plants to 
sp>read and grow freely ; (2) Tlicy must permit a free circu- 
lation of air ; (3) The water ichich falls upon them must he 
readily ahsorhed, and have, at the same time, such free circu- 
lation, that any swplus moisture loill p)ass off, without hecom- 
ing stagnant, and icithout ivashing away the surface. 

To accomplish these objects, several methods may be pur- 
sued, one or all of which may be employed, as the condition 
of the land, or other circumstances seem to require. Those 
means best adapted to the farming operations of our own 
country will be described in this chapter. 

335. (a) Mixing soils may be resorted to, where those 
of widely-different classes are sufficiently near each other to 
admit of transportation. For example, the best and most 
durable remedy for a stiff clay is the application of sand ; 
while, on the other hand, the best remedy for a very loose, 
sandy soil., is the application of clay. If a farmer has both 
kinds of soil on contiguous portions of his land, he may often 
find it profitable to haul sand upon his stiff clays, and, for 
each load of sand, bring back a load of clay to be applied to 
the loose, sandy surface. This method is extensively and 
most successfully employed in Holland. Clay soils may also 
be greatly benefited by being mixed with peaty soils, or, still 
better, by applying pure peat. So, those of peaty character, 



196 MECHANICAL TREAMENT OT SOILS. 

being often too porous, may be improved with clay, or clay 
and sand together. 

336. (6) Plowing is the most common, and most econo- 
mical means of giving a soil its proper mechanical condition. 
All past experience proves that, without the plow, or its 

, equivalent, successful agriculture is impossible ; while the 
history of the world shows that nations have generally been 
prosperous (other things being equal,) just in proportion to 
the skilful use they have made of this most important of all 
instruments. If two men, with equal force and capital, are 
placed upon contiguous farms of equal size and fertility, they 
will 2'>>'osper very much as they plow. The one who scratches 
the surface to the depth of only three or four inches, will 
soon find both his farm and himself growing poor; while the 
one who is not satisfied with breaking and cultivating less 
than twelve inches in depth of his land, will, most probably, 
soon find it necessary to " pull down his barns and build 
greater." 

337. (c) Repeated p)lowin(j during the growth of many 
crops, not only cleans the land, by destroying weeds and 
gi'ass, but also serves another most important purpose not to 
be overlooked, even if the land is already clean : that is, it 
keeps the soil in a proper condition for the growing roots, 
and for the free circulation of air and moisture. These ad- 
vantages are seen every season, where corn, tobacco, and 
cotton crops are properly cultivated. 

338. ((7) Deep plowing is absolutely necessary on almost 
every farm, in order to get the highest profit from the soil. 
The reasons for this may be rendered plain enough for any 
mind, in a few sentences. (1.) The space in depth, to which 
the roots of crops penetrate, and from which they derive 
nourishment, is limited chiefly by the extent to which the 
plow has run. Beneath that point, especially in clay soils, 
the roots make but little progress. (2.) The unbroken sub- 



MECHANICAL TREATMENT OF SOILS. 197 

soil, when composed of clay, is not easily penetrated by rain. 
Hence, after the plowed mass has become saturated, the sur- 
plus water escapes from the surflice, frequently carrying off 
valuable portions of the fertility, and leaving unsightly 
gullies behind it. Deep plowing tends to prevent icashhig. 
(3.) A deeply-broken soil is a sort of store-house for moisture, 
holding a portion always in reserve for periods of drought. 
When the sun, the air, and the growing crop have taken up 
the surface moisture, some of the roots are still deep down 
in the earth, where the supply is abundant. Then, again, 
this moisture from below constantly rises toward the top 
during drought, by the force of capillary attraction, thus 
keeping up the supply to those roots nearer the surface. 
Besides this, it brings with it some elements of fertility in 
solution, and as the evaporation at the surface goes on, these 
are left to aid in enriching the surface-soil. Drought may 
thus improve land which has been properly plowed. 

339. Sub-soiling. — The sub-soil plow is designed to 
follow the ordinary or surface-plow, in the furrow left by the 
latter. By this means the bottom of the furrow is broken 
and pulverized, without being turned up. The surface-plow 
then throws its next furrow upon this loosened portion of 
the sub-soil ; and, again, the sub-soil plow following, breaks 
another portion beneath ; and so the process is continued 
till the whole field has its surface stirred to a depth which 
cannot ordinarily be reached by any one plow operating 
alone. 

One of the simplest and best sub-soil plows is constructed 
upon the following plan : It has a strong, sharp coulter, 
extending about fifteen inches below the beam, having a 
share, or wing, on one side of it, about two-thirds as wide as 
the share of the surface-plow (Fig. 42, a). The hind part 
of this share-wing should be elevated about three inches, so 
as simply to raise the clay, and let it fall back in a pulverized 
17* 



198 MECIIANICA.L TREATMENT OF SOILS. 




MECHANICAL TREATMENT OF SOILS. 399 

condition behind the coulter. The bar forming the point, 
should extend backward from the heel of the coulter four or 
five inches, to give steadiness to the plow, and enable the 
plow-man to regulate its depth (Fig. 42, h). 

If the plow is to be worked by two horses, which it gene- 
rally requires in a stiff soil, one of the horses should walk in 
the furrow, and the coulter must then run with its share 
directly behind him. In order to throw the coulter thus 
more nearly in the track of the furrow-horse, than of the one 
on the unbroken land, the beam may be made crooked. The 
accompanying figure will give a good general idea of the 
parts and structure of this implement. It can be made by any 
ordinary plow-maker, at a cost of three or four dollars. A 
straight beam will do, if the point of the coulter is inclined 
towards the furrow. But the handles are then thrown too 
far out of the line of draught. 

340. Benefits. — The benefits of sub-soiling are very 
similar to those of deep plowing, already given (§ 338). It 
opens up a new source of fertility, for the sub-soil always 
contains many of the substances demanded by the growing 
crop. It gives a deeper space for the circulation and reten- 
tion of air and moisture, and thus serves as an antidote to 
drought. Again, if the soil is level, and of such a character 
as to retain too much of the water which falls on it, and thus 
becomes swampy, the broken sub-soil lets it pass ofi" more 
freely from the surface-soil, and the sub-soiling thus becomes 
akin to draining. But, on horizontal lands, in case there is 
still a stratum of impervious clay beneath the broken sub- 
soil, there will be no outlet for the surplus water, which will 
then be confined in the level field, as in a shallow basin. In 
such a case, draining must precede sub-soil plowing, else the 
latter will be of no avail. If land is level, then subsoiling 
will be of little service to it, unless it be either naturally or 
artificially drained. 



200 MECHANICAL T R E A T M I-: N T OF SOILS. 

But one peculiar advantage which sub-soiling has over 
ordinary deep plowing, is that it gives a deeply-pulverized 
mass, without exposing upon the surface that portion which 
is often unfit for such a purpose. If, for example, the sub- 
soil is a tenacious clay, which would readily form a hard 
crust on the surface, it had best not be turned up; or if it 
is of a lighter color than the surface-soil, it would not 
absorb heat so freely, and would hence be, in that respect, 
injurious. 

Sub-soiling need not be resorted to in all cases. In very 
deep loamy and sandy soils, it is sometimes better to run two 
ordinary plows, the one after the other, in the same furrow 
— the second being set deeper than the first. In this way 
the surface and sub-soils are inverted, to some extent, or, at 
least, completely mingled • and where the surface has been 
exhausted by long-continued tillage, its place is thus supplied 
by fresh soil. This is called " trench-plowing." 

The sub-soil plow serves a valuable purpose, when run 
through meadows and grass-lands which have become too 
compact. The soil beneath the sod is loosened to a great 
depth, without the sod being seriously broken. This plow 
may also be used for loosening the earth beneath the roots 
of corn, or cotton, before the plant has attained any consid- 
erable size. 

The Harroio and Cultivator are important auxiliaries to 
the plow, in reducing the soil to a more completely pulve- 
rized condition; in mixing fertilizers more entirely with 
it ; in giving a smooth surface ; and in covering the seeds 
of some crops. The cultivator is especially useful in stirring 
the soil between corn-rows, when the roots have become too 
much extended to allow very deep tillage ; and in covering 
wheat, when sown broad-cast. 

The Roller is an important instrument on many soils. 
Where clods are too hard for the harrow to reduce, the roller 



DRAINING. 201 

affords the best means of crushing them. Wlien very light 
soils are cultivated in wheat or grass, the roller is frequently 
wanted to render the surface sufficiently compact. 

DRAINING. 

341. The chief object of draining is to carry off the sur- 
plus moisture from the soil. In our countiy, especially in 
the South and West, where land is abundant, it is confined 
almost entirely to sAvamps, and to such lands as (by their 
level surface and impervious sub-soil, or tenacious strata 
beneath) collect and retain stagnant water. Thousands of 
acres of swamp-lands have by this means been reclaimed 
from a worse than worthless condition, and rendered ex- 
tremely fertile; while millions lie yet unreclaimed, in our 
Southern States, fit now to produce nothing but loathsome 
reptiles and insects, together with fatal malaria, which 
often make much of the surrounding country almost unin- 
habitable. 

342. Will/ are swampy lands mfertile? (1) The stagnant 
water excludes the air, and causes the organic matter so 
abundantly accumulated to be converted into vegetable acids, 
such as the humic and ulmic, in large excess, with small but 
sometimes very perceptible quantities of acetic and tannic 
acids. Such soils are said to be '^ sour," and produce no- 
thing but coarse, worthless vegetation. (2) The air is also 
necessary to keep up the proper chemical activities in the 
soil, in order to produce the required changes in its mineral 
ingredients. Stagnant water prevents this, by excluding the 
air. (3) Swampy lands are cold. Water neither absorbs 
nor conducts heat so freely as soil ; hence lands covered, or 
even saturated with water, are not readily penetrated by the 
heat of the sun. Besides this, the constant evaporation 
which goes on from the surface of such lands, carries off 
heat rapidly. 



2C2 DRAINING. 

343. Draining, then, by admitting the circulation of air, 
promotes the proper kind of chemical changes in both or- 
ganic and inorganic substances, and thus sweetens a sour 
soil ; and, by admitting heat and checking evaporation, 
brings the ground under the warming influence of the sun. 

The decay of organic matter, and consequent generation 
of gases in drained lauds, has the mechanical effect of ren- 
dering their soils more porous, in a short time after the sur- 
plus water has been withdrawn. The winter frosts greatly 
aid in bringing about the same result. 

As soon as drained lands have become sufficiently dry for 
the plow, they should be treated with a free dressing of 
quick-lime or unleached ashes, to neutralize the excess of 
vegetable acids, and then be broken up to as great a depth 
as possible, in order to aid the circulation of air. 

344. Modes of Draining. — There are two modes of 
draining in common use. The one by surface (or opai) 
drains; the other by hUnd (covered) drains. 

345. I. The open drains consist (1) of one or more main 
channels, or ditches, as deep as they can conveniently be 
made, running through the lowest part of the field. A 
natural channel often serves the same purpose. (2) The 
spaces between the main channels are traversed by the 
smaller drains, leading into these, and situated at distances 
apart, varying from 25 to 100 feet, according to the nature 
of the soil. The depth of each cross-drain, if the ground 
is level, should vary — increasing towards the main channel, 
in order to give some ''fall" to the water in that direction. 
(3) The spaces between these have to be cultivated as sepa- 
rate strips or beds. 

346. Advantage. — The only advantage this kind of drain- 
ing can claim, is its 2^i'<'seiit cheapness. 

Disadvantages. — (1) It is not a tliorougli method. The 
drains cannot be made very deep without endangering the 



D U A I N I N O . 



203 



safety of horses and otlier animals ; and the soil can only be 
drained to the depth of the ditches. (2) It wastes land, by 
occupying considerable spaces which might be cultirated, if 
the ditches were covered. (3) Heavy rains carry away much 
of the valuable matter of the soil, through such drains. (4) 
They are very much in the way of convenient tillage. 

347. II. The covered drains. — These are in every respect 
preferable to those above described. They are constructed 
by digging deep ditches parallel to one another, and leading 
into a larger main channel, like the open drains. But, in- 
stead of being left open, a tube or pipe, formed of tiles, is 
laid in the bottom to carry off the water, and the ditch then 
filled up. 

348. The following figures, with their descriptions, taken 
from the ''Patent-Office Reports" for 1856, will give a good 
idea of the construction of covered drains. 

" Draining tiles are made of clay, similar to brick-clay, 
moulded by a machine into tubes, usually 13 inches long, 
and burnt in a kiln or furnace to be about as hard as what 

Fig. 43. « 



a 



^ 



Q' 



are called hard-burnt bricks. They are of various forms and 
sizes. Some are round, with a sole or flat bottom moulded 
with the tile, and are called " sole tiles," as shown in figure 
a ; others are of a horse-shoe form, open at the bottom, to 



204 



DRAINING. 



be laid on the hard bottom of the ditch without a sole, or in 
soft places with a sole or flat bottom of the same material 
with the tile, made separate from it, as shown in figure h. 
For some localities, pipe-tiles, merely of round tubes, as re- 
presented in figure c, are preferred." 

The tiles are generally laid end to end, and the water 
always finds its way in, readily and freely, at the joints. 

" Where there is danger of displacement, by reason of the 
soft condition of the ground at the bottom of the trenches, 
pipe-tiles are often kept in position by means of collars of 
the same material as the tiles themselves, made loosely to fit 
over the joint, as represented in the following cut: 
Fig. 44. 



c 



ex 



'' The size of tiles to be used varies from 2 to 6 inches 
calibre, according to the quantity of water to be conveyed. 
It is a question of expediency whether to use very large 
tiles, or to lay two or more courses of smaller size, side by 
side, when the flow of water is very great. 

349.* "A glance at the following diagrams will give a cor- 
rect idea of the general process of opening and finishing the 
drains with the pipes laid : 

Fig. 45. 





DRAINING. 205 

" Figure o roprescnts a trench cut in clay, ready to receive 
pipe-tiles; and figure h, a section of the same drain finished. 
Figure c represents a section of a finished drain, with a sole 
tile, as usually constructed in common soil." 

350. Where stones can he conveniently procured, the fol- 
lowing method, as described in ''Norton's Scientific Agricul- 
ture," is cheap and simple. 

" The ditch should of course be wedge-shaped, for conve- 
nience of digging, and should be smooth on the bottom. 

"Where stones are used, the proper width is about six 
inches at the bottom. Small stones should be selected, or 
large ones broken to about the size of a hen's egg, and the 
ditch filled in with these to the depth of niiTe or ten inches. 
The earth is apt to fall into the cavities among larger stones, 
and mice or rats make their burrows there ; in either case, 
water finds its way from above, and washes in dirt and mud, 
soon causing the drain to choke. With small stones, choking 
from either of these causes cannot take place, if a good turf 
be laid grass-side down above the stones, and the earth then 
trampled in hard. Cypress or cedar shavings are sometimes 
used, but are not quite so safe as a good sound turf. The 
water should find its way into the drain from the sides, and 
not from the top. The accompanying figure (46) represents 
the arrangement of the stones : a is the turf on 
top; if the water enters at the sides, h, h, it ^^' ' 

comes in clear, having filtered through the soil, 
and deposited everything in the way of mud, 
which might tend to choke the drain. 
In very swampy, soft ground, it is sometimes 
necessary to lay a plank or slab on the bottom 
of the drain before putting in the stones. This 
is to prevent them from sinking, and making 
an uneven bottom, before the soil becomes dry enough to be 
firm." 

18 




20G DRAINING. 

Unbroken stones have been very successfully used in con- 
structing drains. The method of laying such stones, in 
ditches, two feet wide at the top and one foot at the bottom, 
is very clearly stated by Mr. P. Slaughter, in his Premium 
Essay on this subject, submitted to the Virginia State Agri- 
cultural Society in 1854. He says : "A careful hand, in 
choosing suitable stones, places them on each side of the 
ditch as side walls, treading upon them as he goes along, to 
be assured that they are firm in their places. A second 
hand follows, placing flat stones upon these side walls. A 
third fills the spaces with small stones. Another levels the 
surface with still smaller fragments, upon which, straw, 
leaves, grass, of even shavings, are laid in thin layers to ex- 
clude the earth from remaining crevices." 

Timbers — even unhewn poles — have been frequcTitly 
substituted for the stones. Two lines of poles are laid in 
the bottom of the ditch, and a third over the space between 
them. These have been found to last many years, and are 
especially applicable in swamps, where stones or tiles would 
sink. 

351. There are several points to be observed in the con- 
struction of covered drains. (1) What should be their 
direction, with respect to the slope of the ground ? If the 
land is nearly level, the main or cross channel should run 
along the lowest part of the space to be drained by the small 
channels, and should have as much fall as possible towards 
the final outlet of the water from the field. The side drains 
should run at right angles (or nearly so) to this, with as 
much fall as can be given them. If the drained land is a 
hill-side, the large cross drain should run along the base of 
the hill, but have sufficient fall to carry off water freely. 
The smaller drains should run directly down the slope into 
the cross drain. 



DRAINING. 207 

352. (2) How far apart should the drains be placed? 
This depends upon the nature of the soil.' If the soil is a 
very impervious clay, it may be best to place them not more 
than twenty-five feet apart. But if the soil is gravelly or 
peaty, they may often be separated by a space of 50 or 100 
yards. A large field, with a sandy or pebbly sub-stratum, 
may be drained by a single ditch. 

In hilly regions, there are frequently very narrow 
valleys, where the bases of hills come nearly together, form- 
ing strips of land more or less swampy, or at least too wet to 
be productive. The meadows in the Valley of Virginia 
abound in such localities. A single drain, run from end to 
end along each one of these, would generally make them 
productive of either good grass or grain crops. Where they 
are wide, short side drains may be required. 

353, (3) How deep should drains be laid '! At least so 
deep, that the top of the line of tiles M'ill be several inches 
below the lowest depth to which the sub-soil plow can be 
made to run. If the sub-soiling reaches fifteen inches, short 
of which no farmer should be satisfied, and which can easily 
be attained in a few years, by increasing the depth at each 
successive plowing, then the ditches should be at least thirty 
inches. But the great object of draining is to remove the 
surplus water, and give free access of air to as great a dejith 
of soil as possible. Hence, if drains can be economically 
laid at a depth of five or six feet, so much the greater will 
be their benefit. The roots of crops run to a great depth in 
soils which are in a proper physical condition to be pene- 
trated by them, and in a proper chemical condition to give 
them nourishment. Indian corn has been known to send its 
roots to the depth of five or six feet. At a place where an 
opening had been made for the foundation of a house, to the 
depth of about five feet, and afterwards filled up, a most 



208 DRAINING. 

luxuriant buncli of clover was found growing. I had it 
carefully dug out, and found the main root extending to a 
perpendicular depth of forty-two inches. It will generally 
be found that the tops of plants vary nearly in proportion to 
their roots, and by furnishing a deep rich soil for the roots, 
we will ultimately reap an abundant reward from the harvest 
which they j^roduce. 

354. When swampy lands have been drained, they will 
not generally be at once productive. Time must be allowed 
for the proper chemical changes to take place, but these 
changes may be greatly hastened by artificial means. (1) 
Ploicimj, as soon as the ground is sufficiently dry, will aid in 
giving the air free circulation, and this we know to be one 
of the great chemical agencies by which soils are improved. 
(2) The application of caustic lime, or unleaclied ashes, will 
help to neutralize the excess of organic acids generally present, 
and thus sweeten the soil. 

Draining in clay soils is one of the best preventives of 
drought. Stiff soils are generally very wet during the winter 
and spring, and, by their own weight, settle down into a 
compact mass ; and, although the surface-soil may be broken 
up and pulverized, the sub-soil may still be left in its com- 
pact form ; or, if broken up, there will still be a layer below, 
to prevent the free escape of surplus water. In wet weather 
the whole will become like a bed of mortar, and will tend to 
settle down again into its original compactness. Then, in a 
drought, the small quantity of water, which the few remain- 
ing pores can hold, will soon disappear. But, if the surjjlus 
water is let off by drains as soon as it collects, the surface 
and sub-soils will retain their porous character — the larger 
pores being filled with air, and the smaller ones with moist- 
ure, which will be held by capillary attraction, in readiness 
Jor future drought. 



QUESTIONS. 209 



QUESTIONS ON CHAPTER XIII. 

§ 334. In reducing soils to their proper mechanical condition, what 
three points arc to be kept distinctly in view? 

335. When may mixing soils be adopted ? Best remedy for stiff 
clay? Best remedy for loose sand? How may the mixing be 
adopted ? 

336-338. Most common means of reducing the soil ? Is the plow 
indispensable? What connection has its use with the prosperity of 
an individual, or a people? Repeated plowing? Deep plowing? 
Its first advantage? Second? Third? IJow docs it cause moisture 
to circulate ? How docs it increase fertility ? 

339, 340. What is the subsoil? Use of a sub-soil plow? Describe 
the plow represented in Fig. 42. Why is the beam made crooked? 
What is said of the benefits of sub-soiling? When should draining 
accompany sub-soiling? AVhat peculiar advantage has sub-soiling 
over common deep plowing? When is sub-soiling not needed? Use 
of sub-soil plow in grass lands ? What is said of the harrow and cul- 
tioalor? The roller? 

341-343. The chief object of Draining? To which liind of land 
is it chiefly applied iu this country? Why are swampy lands itifer- 
tile ? Influence of stagnant water? How does draining promote 
circulation of air in tlie soil ? IIow does it render the soil wai'mer? 
Effect of dccajing.organic matter? What dressing should be applied 
to drained lands ? 

344-340. IIow many ?7!0(fes of draining? Describe the open drains. 
Advantage of this method? First disadvantage ? Second? Third? 
Fourth ? 

347-350. IIow are covered drains constructed ? How are draining- 
tiles made? AVhat does Fig. 44 represent ? Size of tiles? Explain 
Fig. 45. How are drains made with broken stones ? Explain Fig. 
4G. IIow have unbroken stones been used? Timbers substituted 
for tiles ? 

351-354. First point to be observed in the construction of drains? 
Second point? How may narrow valleys be drained? How deep 
should drains be made? Objects to be aimed at? Depth to which 
roots run ? Will swampy lands be immediately productive after 
draining? What means may be adopted to hasten their productive- 
ness? IIow does draining prevent drought in clay soils? 
18* 



210 CHEMICAL TREATMENT OF THE SOIL. 



CHAPTER XIV. 

CHEMICAL TREATMENT OF THE SOIL. 

355. A SOIL may receive all the attention possible, in tlie 
■way of plowing, draining, &c., and still not be productive. 
It may yet lack some of the proper chemical elements neces- 
sary to supply the wants of the growing crop. By referring 
back to Tabic III. (p. 12.3), we see that the mineral ingre- 
dients taken from the soil by different crops are nearly iden- 
tical in hind, but vary considerably in the j^^oportio^is in 
which they enter into the constitution of the ashes of differ- 
ent plants, or different parts of the same plant. 

356. That a soil may be fertile for a particular crop, 
several chemical properties are essential. (1) It must con- 
tain a sufficient excess of the mineral elements required by 
the crop, to allow the roots to find an abundant supply within 
the limited spaces which can be reached by the rootlets. 
Of course, this would require in the whole mass of the soil, 
much more of each clement than could be removed by a 
single crop. (2) The 2^^(^nt-food must he in the proper che- 
mical and physical condition to he tahcn vp) and appropriated 
hj the jilants. Silica, in the condition of sand, cannot act as 
a fertilizer, because of its insolubility; but, in such combina- 
tions as render it soluble, it is one of the most important 
elements of nutrition for plants. (3) The soil must he free 
from an ivjurioiis excess of any of the elements of fertility. 
Too much magnesia, or even too much carbonate of lime, 
may be injurious ; as in the chalk lands of England, Avhich 
are among the least productive of that country. The acids 
in humus are useful to a certain extent, but in large excess 



CHEMICAL TREATMENT OF THE SOIL. 211 

they become injurious (§ 342). (4) Organic matter is essen- 
tial to a high degree of fertility. In a soil having the proper 
mineral elements alone, a plant may come to maturity, and 
hear seed, obtaining the necessary organic food from the air, 
through its leaves and roots ; but a full crop cannot be ex- 
pected in such a case. The soil, to be fertile, must contain 
both humus and ammonia. 

357. The analysis of a soil is not always sufficient to de- 
cide the question whether it is fertile or not. The per cent 
of some ingredients taken from the land, by even several 
successive crops, is so extremely small, that the most delicate 
chemical tests would barely indicate traces of their presence. 
Far less than one per cent of phosphoric acid, or chlorine, or 
potassa, or lime, would be sufficient for all the crops that 
could be cultivated on a soil for many successive years. Even 
one-hunched fh of one per cent is more than sufficient to sup-^ 
ply many crops. But chemical analysis can detect far less 
than this, and yet not be able to say positively whether the 
soil is fertile or not for a particular crop ; for the substance 
may be present in sufficient quantity, but not in the proper 
condition to be used by the plant. Chemistry is not able, 
in every case, to say in what combination elements exist in 
soils, where the proportions are extremely small ; much less 
has it been able to tell us in what combinations the plant 
takes up its mineral food. Still, this valuable science has 
thrown much light upon the relation subsisting between the 
soil and the crop. 

Analysis tells us, in the first place, that productive soils 
always contain the same mineral matter found in the ashes 
of the plants which grow upon thciu. In the second place, 
it tells us which elements of fertility exist in very minute 
quantities, and which in abundance, and then points to the 
sources from which we may supply those in which the soil is 
deficient; but it cannot ahvays predict the influence which 



212 CIIEIMICAL TREATMENT OF THE SOIL. 

a particular fertilizer is to have upon the crop to which it ia 
applied. It frequently tells us, too, when an injurious excess 
of any substance is present, and what applications are to be 
made, to counteract the influence of such substance. 

858. We shall place side by side, in the following table, 
the analyses of three soils, difi'ering in quality. The first 
is fertile for all ordinary crops, without manure. The reason 
of this will be seen in the presence of an abundance of those 
substances found in the ashes of plants. The second is a 
soil Avhich produces well, with the apjilication of gtjpsum 
(furnishing lime and sulphuric acid) and ashes (furnishi)ig 
potassa, lime, etc.). The deficiencies in the table are thus 
filled up. The tldrel is a poor soil, requiring much manuring. 
Observe in how many ingredients it is deficient. 



TABLE V. 

In 100 lbs. of soil. Fertile. ^^■i'.,","'' "'",'.. „""'* Infertile. 



Fertile ivith ashes 
and f:ypsum. 

Organic matter 10.00 5.00 COO 

Potassa 0.40 0.01 (clef.).... Deficieut. 

Soda 0.20 0.20 Deficient. 

Lime 5.90 1.80 0.50 

Magnesia 0.80 0.70 0.80 

Oxide of iron 2.10 4.10 8.00 

Oxide of manganese. ... 0.10 0.30 1.00 

Alumina 10.70 25.60 25.30 

riiosplioric acid 0.40 0.20 Deficient. 

Sulphuric acid 0.30 Deficient Deficient. 

Carbonic acid 5.20 1.40 0.50 

Silica 63.90 60.00 58.00 

Chlorine 0.02 0.07 Deficient. 

359. It will be seen, from the first column of the above 
table, that even a fertile soil may have but a small percent- 
age of several ingredients which are absolutely necessary in 
the production of every crop. No crop, for example, can be 
be produced without potassa and phosphoric acid ; and yet 
these form a very small proportion of any ordinary soil. A 



CHEMICAL TREATMENT OF THE SOIL. 213 

single crop takes away but little of any one element of fer- 
tility; but still, reiDcated cultivation of similar crops for many 
years, must greatly diminish the supply of those mineral ele- 
ments found in the ashes of such crops. 

Every bushel of wheat, every hogshead of tobacco, every 
ton of hay, and every bale of cotton sold, carries with it a 
portion of potassa, lime, phosphoric acid, and other mineral 
matter. Every fatted ox carries with him to market a good 
many pounds of phosphate of lime, which came from the soil 
on which his food was produced. 

360. If every article of produce sent to market carries 
with it a portion of the mineral fertility of the farm, this 
must in some way be restored, else the land must become 
poor. Some soils may contain all the mineral elements of 
fertility in such abundance, that even centuries of cultiva- 
tion would not exhaust them entirely; but such is not gene- 
rally the case. Some of the fields in the central and north- 
ern parts of Kentucky, have been cultivated for more than 
half a century without manure, and are still fertile. Some 
of the James river bottoms, in Virginia, have been cultivated 
for more than a century without manure, and still produce 
well. But we must not draw general conclusions from a few 
extraordinary cases. The general experience of the world 
is, that lands become exhausted hy lowj tillage icithout 
manure. 

361. The organic, as well as the inorganic, matter is ex- 
hausted by improper cultivation. The humus of the soil is 
decomposed, and gradually disappears; and unless fresh por- 
tions are supplied from time to time, a deficiency must be the 
result. The ammonia is still more rapidly exhausted. The 
natural supply of ammonia in soils is not generally abundant, 
while its volatility and chemical activity, cause it to be con- 
stantly escaping, or undergoing changes of form and combi- 
nation. Hence, we see the necessity for artificial fertilizers. 



21-1 FERTILIZERS, 

FERTILIZERS. 

362. A fertilizer is any substance which, ajyplicd to a soil, 
will preserve or increase its productiveness. 

363. From what has been said of the origin of soils, and 
of their -^^xo^ex p)]ii/sical and chemical condition, we infer that 
they may demand fertilizers : 

a. From original infertility. If the rocks* from which 
the soil is formed have not the required elements of fertility, 
they must be supplied from other sources, before the land can 
become productive. Exs. Granite soils generally require 
lime. Limestone soils are often deficient in potassa. 

h. From the presence of some substance inncholesome to 
crops. We have seen that too much water is injurious. The 
remedy in such a case is draining. Organic acids we have 
also found to be injurious, when in excess, as is generally the 
case in swampy lands. 

c. From exhaustion by long-continued cultivation. The 
reasons for this have been already given; and we have illus- 
trations of it in all countries where the lands have been tilled 
for many years without proper application of manures. 

d. From too lo)ig application of the same fertilizer. If a 
soil is deficient in only one or two of its proper elements, and 
these are supplied, its fertility may be at once restored. But 
if the application of these same substances alone, be made 
for several successive years, they will be found in many cases 
to cease having their former influence, and will appear to 
prove injurious rather than beneficial. Such has been the 
case with many a field in the Valley of Virginia, under the 
influence of oft-repeated applications of gypsum alone. 

To understand the reason of this, we have only to remem- 
ber, that, while we are applying one or two elements of fer- 

*By "rocks" we mean all solid mineral matter wbich, by disin- 
tegration, helps to form soils. 



FERTILIZERS. 215 

tility to the soil, we are taking away many others. Gypsum 
can suj^ply lime ami sulphnric acid, but it cannot supply 
potassa and phosphoric acid. By applying gypsum, then, 
year after year, we may accumulate a large excess of its own 
elements, while the soil is becoming poor from the exhaus- 
tion of something else equally necessary, such as potassa or 
phosphoric acid. 

363. Whether, then, we would enrich a barren waste, 
neutralize some unwholesome ingredient of the soil, restore 
exhausted lands, or supply neglected fertilizers, we must re- 
sort to the proper artificial means. To do this intelligently 
requires some knowledge of the various fertilizers; their 
composition, mode of application, influence, etc. 

364. Classification. — Fertilizers naturally form two 
general classes, yforihy 0^ woiQ : (1) Organic manures ; that 
is, such as have a vegetable or animal origin. Barn-yard 
and stable manures, crops plowed down upon the soil, guano, 
etc. come under this class. (2) Mineral manures are such 
as are obtained from the earth, from water, or by burning 
out the organic matter of plants and animals. Gypsum, 
common salt (NaCl), ashes, and bone-earth are examples of 
mineral manures. 

We may with propriety subdivide organic manures into : 
(1) Those which, by their decay, produce chiefly Immus. 
These we shall c^Al ^'•liumlfcrous." * (2) Those which, by 
their decay, produce much ammonia, we shall call " ammo- 
nifero^is." * 

Illustration. — When leaves, straw, and such like substances 
decay, the product is chiefly humus; hence, these are hunii- 
ferous. When the flesh and urine of animals decay, they 

* So far as I know, these terms have not been employed before ; 
but every student of Agricultural Chemistry will see, at once, that 
they are needed in our vocabulary, conveying ideas vrhich could not 
be otherwise expressed without circumlocution. 



210 FKRTILIZERS. 

set free large quantities of ammonia; liencC; these are am- 
moniferous. 

365. Influence of Organic Manures. — They increase 
the supply of organic matter in the soil, and generally have 
a ftivorable influence on both its mechanical and chemical 
condition. (1) If the soil is a stiff clay, the particles of 
humus, mingling with the particles of clay, prevent their 
forming a cohesive mass. The soil being thus rendered more 
loose and porous, is more easily cultivated, absorbs and retains 
moisture better, and is more easily penetrated by the roots 
of plants. The carbonic gas set free during the decay of 
humus, no doubt aids in rendering soils porous. The gas 
being liberated in all parts of the soil, as it is throughout a 
loaf of bread, becomes entangled among the particles, and 
forces them asunder. (2) The increase of organic matter 
gives a darker color to the surface, and thus renders liicarmer 
and earlier. This influence may be readily perceived, by 
observing how much more quickly corn, or other grain, ger- 
minates in those parts of a field where the soil is darkened 
with humus, than it does where the surface is lighter in color. 
In such places the crop generally starts more promptly, and 
at first grows more rapidly, but often fails to be as heavy in 
the end as that which started more slowly ; because, while 
the soil is in a bettter physical condition, its chemical con- 
dition may, in some important particulars, be less favorable. 

366. (2) Organic manures improve the cJicmical condition 
of the soil, by keeping up the supply of humus, which be- 
comes gradually exhausted by repeated tillage. The humi- 
ferous manures do this in part ; but it may, to a great ex- 
tent, be accomjilished by the roots and stubble left upon the 
ground. The other class of organic manures — the ammoni- 
ferous — are still more important. Reasons have been already 
given for the rapid disappeai'ance of ammonia from the soil. 
It is also true of all ammoniferous compounds, that they un- 



FERTILIZERS. 21T 

dergo spontaneous decay with great rapidity, under the in- 
fluence of air, moisture, and heat ; and are, hence, not very 
durahle. They must, therefore, be frequently applied. Then 
a supply of such substances being essential to the vigorous 
growth of almost every valuable crop, we readily perceive 
their great value. In fact, the value of organic manures 
may be estimated chiefly by the quantity of ammonia they 
are capable of yielding. 

367. (3) Besides furnishing organic food in the form of 
carbonic gas, the acids of the humus combine with liberated 
ammonia in the soil, and prevent its escape ('' fix it"). Such 
compounds, being soluble, are probably absorbed directly by 
the roots of the crop, and yield both carbon and nitrogen 
compounds to the sap. These are afterwards elaborated in 
the leaf, and fitted to promote the subsequent growth of the 
the plant. A proper admixture of humus, by fixing ammo- 
nia as it is generated, makes the influence of ammoniferous 
manures more durable than they would otherwise be. 

368. (4) The organic manures do more than simply supply 
organic food to crops. They bring back much of the mine- 
ral matter which they have previously collected from the soil. 
They return this, too, in the form best adapted to meet the 
wants of the plants to be nourished ; for they have already 
been subjected to the modifying influence of vitality in one 
set of plants, and will most probably require very slight 
changes to adapt them to another set. Reasoning from 
analogy, we may conclude that plants take up most readily 
those substances having the form required in their new com- 
bination. The phosphates from the stable and the barn-yard 
are certainly in a better condition to nourish a crop of wheat 
or tobacco, than is the phosphate of lime in bone ashes. 

369. Forms of IIumiferous Fertilizers. — (1) Dri/, 
undecayed vegetable substances, in the form of straic, corn- 
stalks, forest leaves, etc. are often plowed down into the soil. 

19 



218 FERTILIZEKS. 

These gradually undergoing decay, produce a fresh supply 
of humus. From a little albuminous matter which they 
usually contain, a small portion of ammonia is also generated. 
The decay of such substances is slow, and hence an imme- 
diate effect is not to be expected; but the ultimate influence 
is always beneficial, unless there is already an excess of or- 
ganic matter in the soil. If straw, leaves, etc. are thrown 
up in heaps (compost heaps) with other substances, such as 
the scrapings of stables and barn-yards, which will hasten 
their decomposition, and allowed to lie in that condition until 
partial decay has taken place, their benefit to the soil will be 
more immediate. After the process of decay has commenced, 
it will continue to go on rapidly in the soil ; and there will 
be less loss from the escape of volatile matter, than if the 
decay is completed in the heap. 

370. (2) Green Crops, plowed down into the soil upon 
which they have grown, make one of the cheapest, as well 
as most efficient, means of enriching land. They possess 
Beveral advantages over dry substances of similar charac- 
ter. In the first place, they are already spread upon the 
soil, without the inconvenience of hauling. Secondly, they 
decay more quickly, and sooner become food for other crops. 
Thirdly, they contain a larger quantity of ammoniferous 
matter. The albuminous substances gradually diminish in 
the stalks and leaves of plants, as they approach their period 
of decay, or as their seeds ripen. 

In this country, clover, grasses, buckwheat, peas, oats, and 
some other crops, are plowed down as green manures; but 
of all these, clover is probably the best, especially on lime- 
stone lands. Clover not only produces a good crop above 
the surface, but it produces one still more valuable beneath, 
in the form of roots. The large, fleshy roots of the clover, 
as they decay in the soil, yield both humus and ammonia, 
in considerable quantities. Peas are, perhaps, next in value. 



FERTILIZERS. 219 

The increase of organic matter added to the soil, by plow- 
ing down crops, comes, of course, from the air. Carbonic 
acid and water are taken in by the leaves and roots, and 
converted into vegetable tissues, which by their decay be- 
come hnnius; while ammonia, collected from the air, forms 
the albuminous parts of the plant, and these again generate 
ammonia in the soil. Such roots as run deep, like those of 
clover, bring up mineral matter from a considerable depth, 
and accumulate it near the surface, so that it becomes more 
available for the use of other crops. This is an advantage, 
arising from this process of manuring, not to be disre- 
garded. Sub-soiling aids in this elevation of the mineral 
ingredients of the soil, by allowing the roots to descend "to a 
greater depth. 

There are some soils too light, or too far exhausted, to 
produce clover or grass, which will produce buckwheat or peas. 
By planting and plowing down a few of such crops as these, 
the land may be greatly recruited, and may afterwards be 
treated with clover, if desired, in order to give it still greater 
fertility, or to keep it up to its improved condition. 

371. (3) Peat (the half-decayed vegetable matter col- 
lected in swamps), when thrown up in heaps, and exposed 
to the air for some time — when mixed with lime or ashes, 
and applied to the soil, is a valuable source of humus; and 
when dried and thrown into stables and barn-yards, it forms 
one of the best means of absorbing the liquid parts of animal 
manures, and of fixing their ammonia. The spent-bark of 
tanneries, the scrapings of wood-yards, and the muck formed 
in forests by the decay of leaves, may all be treated in the 
same way. Charcoal and soot (finely-divided carbon) im- 
prove the physical condition of clay soils. 

372. Forms of Ammoniferous Manures, and best 
Means of preserving them. — These are chiefly of ani- 
mal origin, consisting of the excrements of animals, and 



220 FERTILIZERS. 

such refuse niattev as accumulates about slaugliter-liouses 
and fisheries ; also the ammoniacal liquids of gas-works. The 
reasons for attaching a high value to manures of this class, 
have been given (§ 366) ; but to impress a matter of so much 
importance still more deeply upon the mind of the reader, 
the following paragraph is given from Norton. 

" Manures containing nitrogen in large quantity ai"e so 
exceedingly valuable, because this gas is required to form 
gluten, and bodies of that class, in the plant : this is parti- 
cularly so in the seed, and sometimes also in the fruit. 
Plants can easily obtain an abundance of carbon, oxygen, 
and hydrogen from the air, the soil, and manures. Not so 
with nitrogen. They cannot get it from the air [in its free 
form] J there is little of it in most soils ; and hence manures 
which contain much of it produce such marked effect. Not 
that it is more necessary than the other organic bodies, but 
more scarce, at least in a form available for plants." 

373. Excrements. — Under the term " excrement," we 
shall include both the fseces and urine of animals. 

The fseces, or solid excrements contain : (1) Some portions 
of proteine compounds, which soon undergo putrefactive 
decay, and set free ammonia. The quantity of ammonia 
from this source, except in the faeces of hogs, is but small, 
compared with that from the urine. (2) Vegetable fibre iu 
considerable quantities, being the undigested portions of the 
food. This is an abundant source of humus; and on account 
of its predominance over that portion which forms ammonia, 
the fo3ces might with propriety be classed as humiferous 
manure. (3) Portions of mineral substances from the food, 
too valuable to be overlooked, are found in solid excrement. 
Among these, the most abundant are those which are least 
soluble, such as the phosphates of lime and magnesia. 

374. Urine contains about twice as much ammoniferoua 
matter as the same wciuht of fajccs. 'J'hat of horses and 



FERTILIZERS. 221 

sheep is especially rich in ammonia. Some farmers are sufi&- 
eiently careful not to lose the solid portions of the manures 
of their stables and yards, while they take but little pains to 
make provision for having the liquid portions absorbed, and 
thus preserved. They may not be aware that a pint of urine 
from a horse is equal in value to at least three pounds of his 
solid excrement. 

The next most valuable ingredients of urine are the salts 
of potassa and soda. These being soluble, naturally pass more 
readily into the urine, while less soluble phosphates are car- 
ried oif with the solid excrements. 

There are several advantages arising from having these 
two forms of excremcntary matter mixed. Fii'st, it gives a 
pi-oper supply of both humiferous and ammoniferous sub- 
stances. Secondly, it gives the necessary variety of mineral 
matter — phosphoric acid, silica, lime, and magnesia from the 
fasces, with suli)hurie acid, chlorine, and the alkalies, from 
the urine. Thirdly, the presence of ammoniferous matter 
causes rapid fermentation, and consequent decomposition of 
the humiferous matter; and the whole mass is thus more 
quickly brought into the proper state to furnish nutriment 
for the crop. 

375. Fixing Ammonia. — During the fermentation of a 
mixed mass of animal manure, large quantities of ammonia 
escape in the form of a volatile carbonate. This must result 
in great loss of value, unless the escaping substance can be 
arrested, and rendered^ involatile (''fixed"). It becomes a 
question, then, of the highest importance to the farmer, how 
this can best be done. Before we consider the properties of 
the different kinds of animal manures, we must examine a 
little more fully the chemical relations between ammonia 
and certain means which may be employed for its preserva- 
tion (§ 71). and the principles upon which this preservation 
depends. 

19* 



222 FERTILIZERS. 

376. Arresting Fermentation. — What is usually 
termed "fermentation" in heaps of organic manures, is a 
form of spontaneous combustion, which takes place most 
readily and most rapidly in a mass of matter containing con- 
siderable quantities of ammoniferous compounds. The con- 
ditions necessary to this decomposing process are (1), a 
temperature not below 45° ¥.; (2) the presence of a consi- 
derable amount of moisture ; (3) a full supply of air. The 
chief products are carbonic acid gas, water, and ammonia, 
which are volatile; and humus, which is involatile. The 
rapidity of the fermentation (after the three conditions above 
mentioned are fulfilled), depends upon the accumulation and 
retention of the heat always developed by the process. When 
the chemical changes commence in a moist mass of manure, 
which is sufficiently porous to admit the air, the result is 
similar to that which follows the igniting of a mass of com- 
bustible material; while the combustion increases the heat, 
this increase of heat makes the combustion still more rapid. 
But if the burning material is spread out, so that the heat 
will be dispersed, the rapidity of the process is greatly 
checked. So, if a mass of fermenting manure is spread over 
a wide surface, the accumulation of heat is prevented ; and 
if the weather is dry, the moisture is evaporated, and thus 
two of the conditions aifecting the rate of fermentation are 
partially removed. 

Hence we see how sjyreading manure iqwn the surface of 
land, may to a great extent arrest the fermentative process, 
and thus prevent the escape of the most valuable of its con- 
stituents — ammonia and carbonic acid. When manures are 
hauled out and scattered during the Fall and Winter, upon 
clover and grass, or as preparatory to Spring crops, there is 
but little danger of serious loss, except from washing rains, 
which may run over the surface, and carry oif the soluble 
portions of the manure. The extent of the risk in this re- 



FERTILIZERS. 223 

spect must be judged of from the steepness of the land and 
the structure of the soil. 

If the weather of Winter is favorable to the removal of 
stable and yard manures as they accumulate, the cheapest, 
and ordinarily the most convenient way of preserving them, 
is to spread them as soon as possible upon the fields for 
which they are designed. This plan is especially applicable 
to porous lands which are not very steep. The rain then 
carries the soluble portions down into the soil, while the fer- 
mentation of the insoluble portions goes on but slowly, and 
the loss of ammonia is but trifling, compared with what it 
would have been in heaps; unless the heaps had been treated 
with some of the absorbents of ammonia hereafter to be 
mentioned. For something more on this subject, see § 430. 

377. Plowing Down. — If it is found convenient to apply 
animal manures to the soil as soon as they are collected, they 
may at once be spread upon the land, and buried with the 
plow, provided a crop is to be planted very soon. The fer- 
mentation then goes on beneath the soil; and as the volatile 
matter (of which the ammonia is the most valuable part) 
arises, it is absorbed by the clay, the humus, and the mois- 
ture, with which it immediately comes in contact, and is soon 
found by the roots of the crop. The fertilizing action is slow 
in this case, but is long continued ; and the eifects are often 
more marked in the second crop, than in the one imme- 
diately following the application of the manure. An illus- 
tration of this is very common where farmers are in the habit 
of applying to their corn crop, in the Spring, the fresh ma- 
nures collected during the Winter. Such manures are un- 
fermented, and frequently have no great influence upon the 
corn crop ; but if the corn is followed by wheat, the eff'ects 
of the manure upon it are very conspicuous. 

378. It is not always convenient to apply manures to the 
soil as soon as they are collected ; they must, therefore, re- 



22-1: FERTILIZERS. 

main for some time in heaps, subject to fermentative decay. 
By this decay their action is rendered more prompt, and the 
farmer can sooner reap their beneficial effects ; but to prevent 
serious loss, something must be mixed with the fermenting 
mass to fix the ammonia. The following are some of the 
best substances to be used for this purpose. 

(o) Clay and humus, either separately or mixed, have the 
property of rendering large quantities of ammonia involatile. 
Clay alone is generally too tenacious to be conveniently 
mixed with manures ; but when mingled with a large quan- 
tity of decayed vegetable matter, it forms a rich mould which 
may be conveniently used in compost heaps. Humus, under 
the form of peat, muck, etc., contains organic acids which 
readily combine with ammonia, forming involatile compounds. 

Qj) Gypsum is valuable as an absorbent of ammonia. Its 
action is chemical, and has been given in § 71, which the 
student is requested to read in this connection. 

(c) SuJpliate of iron (copperas) acts in a manner similar 
to gypsum. It gives up its sulphuric acid to the ammonia, 
forming an involatile sulphate of ammonia., while the iron 
becomes first a carbonate, then an oxide. The copperas must 
be applied in solution. One pound to four gallons of water 
is sufiicient. It may be sprinkled over the difiierent portions 
of manure as they are thrown upon the heap, or sprinkled 
over the whole before it is thrown up. 

(cT) Acids. — Sulphuric and muriatic acids both have a 
strong afiinity for ammonia. If either of them be diluted 
with twenty parts of water, and sprinkled over a fermenting 
manure heap, the escape of ammonia will be at once arrested 
in every part of the mass to which the acid liquid has access. 

(e) Caution. — Avoid the use of caustic lime with all ma- 
nures containing ammonia. It will expel ammonia from any 
and all of its compounds. Sulphate of lime, on the other 
hand, is beneficial ; carbonate of lime has no effect, while 



QUESTIONS. 225 

caustic lime is ruinous when mingled with ammoniferous fer- 
tilizers (§ 100). Such a mixture may still possess consider- 
able value, and often produces decidedly beneficial effects 
upon growing crops ; but this benefit is independent of the 
presence of ammonia, and is to be attributed either to the 
lime, or to such organic matter as the lime has not removed. 
These circumstances sometimes lead farmers into the mistake 
of supposing that stable and yard manures are improved by 
the lime, while in reality the most valuable ingredient has 
been exjielled from them. 



QUESTIONS ON CHAPTER XIV'. 

§ 355. Why may a -well-plowed soil still be unproductive ? What 
do we learn from Table III ? 

356, 357, 358, 359, 360, 361. That a soil may be fertile, what is 
the first property required ? Why ? Second property required ? 
Illustrate. Third? Example? Fourth? What forms of organic 
matter must a fertile soil contain? What is said of atiali/sis of soils? 
What relation does it show between the ashes of the crop and the 
soil ? What does Table V illustrate ? Explain it. Is a large per- 
centage of every mineral ingredient necessary? AVhat does every 
article sent to market carry with it? What effect will this ultimately 
have upon the soil ? May not soils be cultivated for many years 
without manure? What does general experience decide? AVhat 
becomes of the organic matter of soils? Which escapes most rapidly ? 

362, 363. What is a fertilizer? First cause which renders fertili- 
zers necessary ? Second? Remedy? Third? Reasons? Fourth? 
Explain this. Knowledge required on this subject ? 

364. lloyr ATQ fertilizers classified? Organic manures? Mineral 
manures ? Illustrations ? Subdivisions of organic manures ? Illus- 
trate each. 

365, 366, 367, 368. Influence of organic manures? How do tliey 
influence a stiff clay ? Explain. IIow do they render a soil warmer? 
Illustrate. How do they improve the chemical condition ? Why 
must ammoniferous substances be frequently applied ? How does 
humus fix ammonia? What mineral substances do organic manures 
add to the soil ? 



22G QUESTIONS. 

3G9, 370, 371. First forms of humiferous fertilizers? How do they 
form humus? Influence of stable manures upon humiferous mat- 
ter? y^^hsii of green crops? Their first advantage ? Second? Crops 
most commonly ploughed down? Which are most valuable? How 
do they increase the organic matter of the soil ? Influence on the 
mineral ingredients? What is peat? How does it form humus? 
Spent-bark ? 

372, 373, 374. Chief source of ammoniferous manures? AVhy are 
these so highly valued ? What are included under the term " excre- 
ments " ? First constituent of fceces ? The second ? The third ? 
In what does urine abound? Best from what animals? Illustrate 
its value. What minerals does it contain? Should humiferous and 
ammoniferous manures be mixed ? The three reasons given ? 

375. What is meant by ^^ fixing" ammonia? AVhy is it important? 

376, 377. Explain fermentation in manure heaps. First condition 
necessary? second? third? What are the products? What deter- 
mines its rapidity ? How does spreading check it ? How does spread- 
ing imxnwvQ preserve it? When is there danger of loss from washing? 
What generally becomes of the soluble matter of manures spread oa 
the soil ? What is said of plowing down manures ? What then be- 
comes of the ammonia ? Is the fertilizing action rapid ? How illus- 
trated ? 

378. Why must manures be sometimes thi-own in heaps? What 
advantages from this ? What of clay and humus, as means for fixing 
ammonia? Of gypsum? How does it act (§ 71) ? Sulphate of iron? 
How applied? How does it act ? What acids are mentioned? How 
applied ? What caution is given ? Do the sulphate and carbonate 
of lime act like caustic lime ? Into what mistake do farmers some- 
times fall ? 



SPECIAL MANURES. 227 



CHAPTER XV. 

SPECIAL MANUKES. 

379. The stable manure collected from the stalls of horses, 
is highly valued by all farmers. But the readiness with 
which it undergoes fermentation, and sends off ammonia, 
together with its abundant supply of soluble organic and 
mineral matter, makes it necessary to exercise care in its 
collection and preservation, so as to avoid loss. 

The urine must be kept from running off. (1) This is 
sometimes done by keeping the horses on close plank floors, 
sloping backward from the trough. At the lower edge of 
the floor, a trench or gutter is so constructed as to receive 
the liquid. This trench is kept constantly supplied with 
some absorbent substance, such as dry peat, muck, or spent- 
tan, which will take up the fluid, and, during the subsequent 
decay, will fix the volatile part, and prevent its loss. A little 
gypsum strewed in the trench every day, would make the 
preservation of the ammonia more certain, and also add to 
the value of the manure. The trench should be cleaned 
out, and filled with a fresh supply of the absorbent very fre- 
quently. (2) Another method is to have a firm clay floor 
(which is better for the feet and legs of horses than a plank 
floor), and to keep it well supplied with litter of straw, leaves, 
muck, etc., which will absorb the liquid part of the manure. 
The wet portions of the litter should be removed every morn- 
ing, and, as they are thrown out into the manure-shed, should 
have a little gypsum, humus, copperas-water, or other absorb- 
ent, sprinkled over them, to arrest the ammonia, which will 
begin to escape in a few hours. 



228 SPECIAL MANURES. 

380. It must never be forgotten by the farmer, that how- 
ever well he may succeed in rendering the most valuable 
portion of his compost, or manure heaps involatile, it is still 
very soluble ; and evei'y rain which passes through the mass, 
carries off much of its value. The loss sustained on many 
of our farms, in two or three years, by exposure of manures 
to the influence of rain, would, if saved, be quite sufiicient 
to cover the cost of a few sheds, which would shelter all the 
manures of the farm for twenty years or more. 

The labor of collecting the manure from cattle-pens into 
sheds, is, perhaps, generally too great to make that an eco- 
nomical method of preserving it. Whenever this is the case, 
it should be hauled out and spread upon the soil, before it 
undergoes fermentation, and before its soluble ingredients 
have been washed away by the rain. 

381. JExcremcnts of coivs, sheep, and hogs require no less 
care for their proper preservation than those of horses. Simi- 
lar means may be adopted. The urine of cows is not much 
inferior to that of horses in value. That of sheep is more 
valuable than either; while that of hogs, though abundant, 
is less valuable than any of those above mentioned, but still 
too important to be neglected. Of all domestic animals, the 
hog gives the most valuable solid excrement, which compen- 
sates for the want of value in his urine. The solid excre- 
ment of the sheep is next in value; then that of the horse 
stands next; while that of the cow is inferior to either. Still, 
all are sufficiently useful to be worth preserving. 

382. Human Excrement requires special attention : (1) 
Because of its high fertilizing value ; and, (2) Because of 
the little regard paid to it by the majority of families. When 
compared with the exeremcntary matter from other animals, 
that of man stands above all, except perhaps that of well-fed 
sheep and fowls. The urine has a much higher value than 
the faeces. " Very accurate analyses have shown that the 



SPECIAL MANURES. 229 

amount of urine contains double the quantity of phosphoric 
acid, four times as much azotizcd [ammoniferous] substances, 
and six times as much alkalies and alkaline salts, as the solid 
faices. Hence, therefore, it follows that the former possesses 
a far higher value than the latter, and deserves to be most 
carefully collected 

" From the preceding observations it may be incidentally 
perceived what an immense capital is lost in large cities, 
where the greater proportion of urine runs into the sewers 
and drains." — Stockhardt. 

Arrangements may easily be made about every country 
dwelling for the careful collection and preservation of this 
valuable kind of fertilizing matter. The simplest methods 
are, to have, in the first place, a compost heap of vegetable 
mould, the scrapings of wood-yards, &c., at some convenient 
place, under shelter, upon which all the slop from chambers 
may be thrown. Let the heap receive occasionally a fresh 
layer of material, and a free application of gypsum. This 
will keep down all disagreeable odor. Then, in the con- 
struction of privies, let the vaults be above ground, large, 
and so arranged that they can be kept constantly charged 
with such absorbent substances as are used in the above 
compost heap. This should be renewed frequently, and what 
is removed from time to time be thrown upon the compost 
heap. A little dilute acid, copperas water, or gypsum, should 
be applied to the vaults frequently, to keep down unpleasant 
odors and preserve ammonia. 

383. GrUANO. — This fertilizer, which is now so extensively 
used, is the excrement of birds which feed chiefly upon fish, 
and have their habitations upon rocky, desolate islands and 
coasts. It has been stated (§ 217) that the urine of birds is 
solid. Guano, then, is a mixture of the urine and faeces of 
birds. From the quality of the food upon which these live, 
we would naturally expect to find in their excrements large 
20 



230 SPECIAL MANURES. 

quantities of ammoniferous compounds and phosphates. Ana- 
lysis shows that these are the most abundant and most valu- 
able ingredients of guano ; while experience proves that the 
most valuable varieties are those which contain the largest 
per cent of salts of ammonia. The best guano is found in 
localities where rain seldom falls — where the ammonia salts 
have not been washed out. Parts of Peru, and the islands 
lying along the coast of that country, are seldom visited by 
rains. Here immense beds of guano, which must have re- 
quired thousands, and probably tens of thousands of years 
for their accumulation, are found in great numbers. The 
deposits of guano are vast stores of ammonia, which a kind 
Providence has been treasuring up through many centuries 
for the use of man. While the rivers have been carrying 
off the ammonia from the land in vast quantities, either in 
solution or in the form of dead animals and insects, the sea- 
birds have been bringing it back in the form of fish ; and 
thus we have another of those compensating arrangements, 
by which the balances of nature are kept properly adjusted. 
The reader must be struck, too, with the analogy between 
these deposits of agricultural wealth, and the great deposits 
of mineral wealth laid up in past ages, in the extensive coal- 
beds found all over the world. In Peru and her adjacent 
islands, there are supposed to be many millions of tons of 
this rich fertilizer yet undisturbed. The African, Chilian, 
and Mexican guanoes are not so valuable as the Peruvian, 
because of their having been more exposed to rains. 

884. The following table gives about the average compo- 
sition of several varieties of guano. 



SPECIAL MANURES. 231 

TABLE VI. 

In 100 parts of Guano are found Peruvian. Chilian. African. 

Water 9 12 20 

Salts of Ammonia and other organic matter 60 50 38 

Phosphates 20 28 26 

Salts of Soda and Potassa 5 6 10 

Carbonate of Lime .^ 4 2 3 

Sand and Clay 2 2 3 

100 100 100 

385. The ammonia of guano is combined chiefly with or- 
ganic acids, such as the uric and humic, forming urate and 
humate of ammonia. These, by exposure to air and moist- 
ure, are gradually converted into the volatile carbonate of 
ammonia, the presence of which is readily perceived on 
opening a bag of Peruvian guano. Hence, if it is to be 
kept on hand for some time, a dry, close place is best for its 
security. 

386. Application. — In applying a manure so costly as 
guano, the greatest economy should be carefully studied. All 
real economy in such cases, consists in such management as 
will realize the largest income from the least expenditure of 
money and labor. The economical use of guano demands, 
(1) the application of the smallest quantity required to 
accomplish the object in view; (2) such treatment of it as 
will secure it against loss, either before or after it is applied; 
(3) a judicious regard to the ultimate improvement of the 
soil. 

The quantity varies with the quality of the soil, and the 
kind of crop. For wheat and corn, from 100 to 300 pounds 
per acre is generally a sufficient quantity ; but every farmer 
should decide questions like this for his own soils, by nume- 
rous experiments. Small quantities may often be most eco- 
nomically used, by being mixed with other manures. This 
is especially the case where the guano is to be brought di- 
rectly in contact with the seeds in the soil. But the labor 
of mixing thoroughly is, in many cases, greater than the 
advantages Grained. 



232 SPECIAL MANURES. 

The most common method of applying guano to wheat, is 
to sow it upon the wheat, and harrow or plow both into the 
soil together; or, when the wheat is drilled, to drill the 
guano with it. To make such applications safe to the grain, 
very minute portions only must be allowed to come in con- 
tact with each separate grain of wheai?^ When applied in 
the hill with corn, cotton, potatoes, or any other crop, it is 
best to '* dilute " it with other substances. The following 
general directions may be of use to guide the young farmer 
to successful experience. 

387. (a) As soon as the bags are opened, the lumps should 
be carefully pulverized by the use of any convenient instru- 
ment, such as a pestle with a broad base. To separate such 
parts as may not be fully reduced to powder, a sieve may be 
used. This should be done just before it is to be applied, so 
that it may not be long exposed. If the lumps are very 
hard, it is best to moisten them, and let them lie in a heap 
several days. 

(6) When the guano is to be mixed with something else, 
some form of humus, or rich vegetable mould, serves well 
for this purpose. Spread a layer two inches deep, of moist 
mould, upon a floor of boards or earth, and over this a layer 
of guano half an inch or an inch thick, with a free sprink- 
ling of plaster. Then add another layer of mould and an- 
other of guano and plaster, in the same order, until as much 
has been employed as is wanted for use. Mix the whole 
mass carefully with a shovel ; or, if a more perfect mingling 
is desired, pass it through a coarse sieve. Such a mixture 
preserves the guano, and puts it in a good condition to be 
applied to almost any crop. 

* A conveuient method of moistening the hiraps, is to dip the un- 
opened bags into a large tub of hot water for 5 or 10 minutes, and 
then lay them up in piles, or stacks, for two or three days, till they 
arc thoroughly penetrated by the moisture, and incipient fermenta- 
tion takes place. This will relax the lumps completely. 



SPECIAL MANURES. 233 

(c) The effects of guano have been found to be more ener- 
getic, when it is dissolved in dilute sulphuric acid. About 
twelve or fifteen pounds of acid, and ten gallons of water, 
poured upon 100 pounds of Peruvian guano, would decom- 
pose the organic salts of ammonia, and form the sulphate of 
ammonia, which is a most energetic fertilizer; and, at the 
same time, another portion of the acid would so act upon the 
phosphate of lime present, as to convert it into the more 
soluble super-phosphate (§§ 395 and 406). 

(rZ) In whatever condition guano may be employed, it 
should be thoroughly incorporated with the soil. This will 
tend to preserve its ammonia, and will so distribute its par- 
ticles, that some of them will be found by the roots of the 
crop in every part of the soil. 

388. Action of Guano. — Some formers say that guano, 
while it produces fine crops for a few years, ultimately ex- 
hausts the soil. In the opinion of many, this results from a 
kind of stimulating influence which it produces upon plants, 
causing in them a kind of artificial or forced growth, by 
which they take away from the soil more fertilizing matter 
than the guano has brought into it. This influence has 
been compared to the influence of alcohol on the human 
system. But, as guano contains nothing which is not an 
appropriate article of nutrition for plants (real food), such a 
comparison is rather absurd. It has also been satisfactorily 
shown, that an ordinary application of guano gives more 
mineral matter to the soil than the resulting crop takes 
away,* at least so far as some of the mineral ingredients are 
concerned. But when we remember that guano continues 
its influence through several successive crops, the quantity 
of some of the mineral substances of the soil may, in the 
meantime, be diminished more than they have been pre- 

* See Dr. P. B. Pendleton's "Essay on Guano." — Proceedings of 
Virginia State Agricultural Society, Vol. III., p. 39. 
20* 



234 SPECIAL MANURES. 

viously increased by the guano. This is especially true of 
potassa, lime, and sulphuric acid. In such cases, the long- 
continued application of guano to some soils may exhaust 
their supply of mineral fertilizers, at least the supply of 
those in the proper condition to be taken up by the roots of 
plants (§ 356). 

The long-continued application of guano exhausts the 
humus of the soil. While guano has an excess of ammonia, 
it has but little humiferous matter in it; and, while the 
caustic character of the ammonia hastens the decomposition 
of humus already present, the loss is not made up from 
the guano. But if we mix with it leached ashes, plaster, 
and humus, there can be but little danger of injury ever 
resulting from its application ; while a corresponding im- 
provement will be the general reward. 

389. The best method of using guano for the permanent 
improvement of soils, is to employ it in connection with green 
manures. It greatly increases the growth of clover, peas, 
&c. ; and when these crops are plowed down, they not only 
carry back with them the mineral matter of the guano, but 
add largely to the supply of humus and ammonia in the soil. 
The guano thus has the power of causing plants to convert 
the carbonic acid and water of the air and soil into humife- 
rous compounds, much more rapidly than they would have 
done if the guano had not been applied. It also causes the 
same plants to thrust their roots more deeply into the sub- 
soil, and thus bring up an increased supply of mineral matter 
in the proper condition to feed succeeding crops. 

390. A great deal of swindling has been practised in the 
sale of guano. The best safeguard against being imposed 
upon, is to buy only from i-cUahle men, regularly engaged in 
the business of selling it. But in case the quality is sus- 
pected, one or two simple tests may be useful in removing or 
confirming suspicions. Exps. — Burn 100 grs. to ashes in a 



ANIMAL COMPOUNDS. 235 

crucible, or iron spoon. The remaining ashes should not 
weigh more than from 35 to 45 grs., and should be nearly 
all soluble in dilute muriatic acid 2. Hub a little of the 
guano with a few grains of freshly-slacked lime, and if a 
strong odor of ammonia is not given off, the quality is not 
good. 

391. Domestic Gnano may be collected about hen-roosts, 
and, although not equal in value to the same weight of the 
Peruvian, it is still the most powerful fertilizer produced 
upon our farms. It should be carefully collected, and 
treated in the same way as guano. 

ANIMAL COMPOUNDS. 

392. The refuse of slaughter-houses and fisheries consists 
of blood, entrails, hair, and other animal compounds, all of 
which contain the elements of ammonia in large quantities, 
and also a considerable amount of soluble mineral salts. 
Hence they possess a high agricultural value. They should 
be mixed with humus, and kept under shelter till they can 
be applied to the soil. If an animal dies on the farm, it 
may be made less offensive by being buried in a mass of 
humus and clay, which will soon be highly charged with 
ammonia from the decaying animal, and will serve to enrich 
some poor spot on an adjacent field. 

Fish are caught in many places, and used for manure. 
They soon decay, and set free ammonia abundantly. 

Insects of various kinds make their habitations in the soil. 
By eating vegetable substances, they help to collect and con- 
centrate the ammoniferous portions of their food ; and when 
they die, their remains add something to the fertility of 
ground in which they are buried. 

393. Bones yield ammonia by the decay of their gelatinous 
substance (§ 204), which makes them a valuable source of 
this important element of fertility. We have also learned 



23G A N I M A L C O JI I' O U N D S . 

that their mineral part is chiefly phosphate of lime, which is 
well adapted to almost all ordinary crops. 

394. Value. — Bones, when dried and ground to powder 
without burning, are inferior only to good guano, in agricul- 
tural value. They yield about half as much ammonia, about 
f7cice as much phosphoric acid, and about three times as 
much lime. Hence, their value in the form of bone-dust is 
more than half that of guano. 

When applied alone, their effect is much slower than that 
of the guano, but much more durable. This is owing to the 
fact that the gelatine undergoes decay more slowly than the 
ammonia salts in guano. In fact, the ammonia of the latter 
is already, to a large extent, ready to afford food for the 
plant, while the ammonia of the former is yet to be gene- 
rated from the decaying gelatine. The phosphate of lime, 
too, seems to require thne to adapt it to the nutrition of crops 
(§429,.). 

395. If bone-dust is treated with an excess of sulphuric 
acid, the phosphate gives up a portion of its lime to the acid;, 
forming sulphate of lime, and a superphosphate of lime is 
thus left, which is much more soluble than the ordinary 
bone-earth, and is hence a much more energetic fertilizer. 
The gelatine of the bones is at the same time reduced to a 
pulpy mass, which soon undergoes decay in the soil, and 
generates ammonia. While the gelatine is not injured, the 
phosphate is greatly improved by being thus treated. 

396. Preparation. — " To every 100 pounds of bones, 
about 50 or 60 of acid are taken ; if bone-dust is used, from 
25 to 45 pounds of acid are suflBcient. The acid must be 
mixed with two or three times its bulk of water, because if 
applied strong it would only burn and blacken the bones, 
without dissolving them. 

" a. The bones are placed in a tub, and a portion of the 
previously-diluted acid poured upon them. After standing 



ANIMAL COMPOUNDS. 237 

a day, another portion of acid maybe poured on; and finally, 
the last on the third day, if they are not already dissolved. 
The mass should be often stirred." 

" h. Another good way is to place the bones in a heap, on 
any convenient floor, and pour a portion of the acid upon 
them. After standing a day, the heap should be thoroughly 
mixed, and a little more acid added : this is to be continued 
so long as necessary. It is a method which I have known 
to prove very successful 

Application. — '' A convenient method, in most cases, is 
to thoroughly mix the pasty mass of dissolved bones with a 
large quantity of ashes, peat-earth, sawdust, or charcoal dust. 
It can then be sown by hand, or dropped from a drill-machine. 
Two or three bushels of these dissolved bones, with half the 
usual quantity of yard manure, are sufficient for an acre."— 
Norton. 

Some who have tried this method, contend that it will not 
succeed well, unless the bones are first broken into fragments, 
then boiled in water — the sulphuric acid being added while 
the water is still hot. The bones and boiling water must be 
thrown together into a large wooden vessel before the acid 
is added, as the acid would rapidly corrode the kettles used 
in the boiling process.* 

* " To DISSOLVE Bones. — If no mills are accessible, bones may be 
dissolved in sulphuric acid. For 100 pounds of bones take about 30 
pounds of acid (2 gallons), and mix with it say 32 pounds of water 
(4 gallons). First put the water into a strong wooden-hooped cask 
or barrel, and add the acid slowly, stirring it, as added, with a stick. 
Crack the bones or not, as may be convenient, and put them in and 
above the fluid. Punch them down, and stir them occasionally with 
a stick. Let them stand four, six, or eight weeks, until softened 
and mostly dissolved. Many assert that they cannot dissolve whole 
bones, but they do not take time enough. From repeated trials, we 
know they ivill dissolve. The time will depend upon the dryness of 
the bones, and their freedom from fat. After standing two months, 



2S8 MINERAL FERTILIZERS. 

MINERAL FERTILIZERS. 

397. While the mineral fertilizers are less important thaa 
the organic, they still serve valuable purposes on many soils. 
A soil may contain even a large excess of some mineral sub- 
stance required by a particular crop, and yet that crop be 
benefited by the application of that same substance under 
some other form. Granite soils, for example, contain potassa 
in abundance, and yet the productiveness of these soils is 
generally increased by the application of potassa in any solu- 
ble form. The reason of this is obvious : the potassa of 
granite is locked up in its insoluble mica and feldspar. In 
hornblende granite (syenite) there is an abundant supply of 
lime, potassa, and silica. Now, these are the chief ingre- 
dients of value in ashes, but these soils are generally very 
much benefited by the application of ashes alone. The sye- 
nite yields its mineral matter but slowly, in a soluble form ; 
while the ashes supply the same ingredients, just ready for 
the plant. 

398. Besides providing food directly for the crop, the 
mineral fertilizers often exert a beneficial influence upon 
mineral and organic substances already in the soil, and also 
absorb the organic food contained in the air. 

Of the chief mineral manures employed in our own coun- 
try, we must take some special notice. Their forms quid 
conditions, the best methods of applying them, and their 
effects, will be the principal points to be noticed. 

more or less, mix the mass thoroughly with six or eight times, or 
more, its bulk of muck, or even with common soil, if need be. This 
makes an excellent fertilizer, worth anywhere all it costs, and more. 
Sulphuric acid, in carboys of 120 to 160 pounds, costs from 2 to 3 
cents per pound, according to distance from the manufactory. It 
needs to be handled with care, as it is corrosive to the flesh and 
clothing." — AinciKOii AyrkiiUurial. 



LIME. 239 

LIME. 

399. Lime is found in every crop, and must, therefore, 
exist in every cultivated soil. And in order to be of service 
to the crop, it must not only be present, but must be in a 
suitable condition to be taken up by the roots, and made 
available to the growing plant. If there is not a sufficient 
excess of available lime present, or if it should be wanted 
to act upon something already in the soil, it may be applied 
in several different forms. 

400. (a) Caustic Lime, prepared from limestone or oyster- 
shells, should be slacked before it is applied, since the pul- 
verized condition makes it more easily spread. It is better, 
ordinarily, to apply it frequently in small portions, than to 
apply large quantities at one dressing. The quantity must 
be determined by the character of the soil. Every farmer 
should make experiments for himself, beginning with from 
20 to 50 bushels per acre, uniformly spread, and increasing 
the quantity as he may find necessary. Recently-drained, 
swampy lands require larger doses. 

401. Effects. — (1) Caustic lime combines with free or- 
ganic acids in the soil, and thus sweetens sour soils. With 
these acids it is supposed to form soluble salts, which are 
valuable as food for crops. (2) It hastens the decay of 
vegetable fibre in the soil, and reduces it to a nutritious 
form — changes it to humus. (3) It sets free ammonia, 
which may exist in some inert condition in the soil, and 
thus indirectly hastens its absorption by the crop. (4) It 
decomposes some mineral substances already present^ and 
makes their elements more available to plants. 

402. Cautions. — It must' not be forgotten that the too 
frequent application of lime, especially to clay soils, may so 
far exhaust the organic matter, as to cause a deficiency in 
this important part of every fertile soil. Its efiects upon 



240 LIME. 

manures containing ammonia, make it unsuitable to be mixed 
with such manures, or even to be applied near the same 
time. 

403. (h) Mild Lime. — When caustic lime has been exposed 
to the air for some time, it gradually combines with carbonic 
acid, and loses its caustic character; it becomes mild lime. 
Ux^y. Pour a little dilute acid or strong vinegar upon lime 
which has lain a good while in the open air : a brisk eflPer- 
vescence will take place, showing that it has become a car- 
bonate. It has the same composition as ordinary limestone, 
but is much superior to the latter, because it is reduced to 
an extremely fine powder, and hence more readily dissolved 
by rain-water containing carbonic acid gas (§ 102). 

404. Effects. — Besides affording nutrition directly to the 
growing crop, it has an effect upon the stronger organic acids, 
similar to that of the caustic lime. These acids are capa- 
ble of removing the carbonic acid, by taking its place iu 
combination with lime ; and thus the organic acids become 
neutral. 

405. ((') Phosphate of Lime. — The phosphate obtained 
by burning bones has been alluded to (§ 204). Besides being 
the chief source from which the quantity of phosphoric acid 
in the soil is increased, it also adds to the supply of lime. 
When the organic matter has been burnt out of bones, they 
are easily reduced to a fine powder, by pounding or grind- 
ing; and may be sown by hand, or mixed with other ma- 
nures. Bone-earth seldom has an immediate effect upon 
cereal grains. Its chemical condition seems to require some 
modifications, before it is well fitted to nourish such crops. 
Hence, the effects are often more marked upon the second 
or third crop, after the application is made, than upon the 
first. If treated with sulphuric acid, as prescribed for un- 
burnt bones (§ 396), the action is much more pi'ompt, and a 
smaller quantity will serve for a single dressing. 



LIME. 241 

406. SiqyerjjhospJiafe of Lime. — By mixing bone-dust and 
guano together, and treating the mixture with sulphuric 
acid, a mixture of sulphate of ammonia from the guano, 
and of superphosphate of lime from both the bones and the 
guano, is formed, ■which has proved to be a most energetic 
manure. Such mixtures are frequently sold under the name 
of " improved sixperphosphates." 

Guano of inferior quality, containing a large percentage 
of phosphates, and but little ammonia, is now extensively 
employed, by mixing it intimately with some good Peruvian 
guano. The mixture is called " manipulated guano." There 
is so much room for imposition in all such artificial manures, 
that farmers should be cautious as to the source from whence 
they come. Buy only from reliable men. 

407. When bones have been burnt in a close vessel, they 
form hone-hJack, or animal charcoal. In this, the animal 
matter has been reduced to carbon in extremely fine division. 
This greatly increases its absorbent power while dry ; and 
when mixed with decaying organic manures, it takes up a 
large c{uantity of ammonia. 

408. (d) Gypsu:m. — This is a source of both lime and sul- 
phuric acid. Its composition and properties have been so 
frequently alluded to already, that a very few additional 
remarks will be sufficient. 

Effects. — (1) It furnishes both of its ingredients (lime 
and sulphuric acid) in a soluble form ; and, as these are re- 
quired by nearly all crops, its direct influence would be to 
supply them (one or both), if deficient in the soil, in an 
available form. It is especially applicable to the grasses, 
including corn and wheat, and to potato and tobacco crops 
(see Table III). (2) Its effects on most crops may be attri- 
buted, perhaps, chiefly to its property of collecting and fixing 
ammonia. 

409. (e) Marl. — The terra ''marl" is used somewhat 
21 



242 LIME. 

indefinitely. In the valley of Virginia, as well as in many 
other places, the porous masses of carbonate of lime deposited 
by limestone springs, are called marl. These are known in 
mineralogy as calcareous tufa. Mixtures of carbonate of 
lime with clay, sand, and other impurities deposited in a loose 
form by water, are also called marl. When such deposits 
are composed largely of shells, infusoria, and organic matter, 
they are generally known as '' shell-marl." Alkaline salts 
are common in shell-marl; and among the organic matter, 
some ammonia may generally be detected. They also con- 
tain some sulphate and phosphate of lime. The presence of 
such a variety of valuable ingredients, makes this species of 
marl a very cifective fertilizer. The marls found in the ter- 
tiary strata of the tide-water region of Virginia, as well as 
those found in other localities, have proved very beneficial 
as manures. In some sections they have formed the hasis 
of a system of improvement, which has done much to reclaim 
many exhausted farms. — (See Riiffiiis Essai/ on Calcareous 
Ilamtres.') 

410. (/) Silicate or Lime. — This compound probably 
plays a more important part as a fertilizer, than many per- 
sons suppose. It is found to some extent in almost all soils. 
As one of the constituents of hornblende and trap rocks, it 
has been already mentioned. In the process of burning 
lime, some portions of it are formed by the silica (almost 
always present to some extent in limestones) uniting with 
lime. 

Effect. — By the combined influence of moisture and car- 
bonic acid, the silicate of lime is slowly changed into the 
carbonate, while the silica is set free in a wlahlc form, so 
that it can be taken up by the roots of plants. The groat 
value of soluble silica will be perceived, when we reflect 
upon the extent to which it enters into the composition of 
the ashes of the stalks, cspcciallv of the cereal grains and 
Lay (see Table III). 



MAGNESIA ASHES. 243 

MAGNESIA. 

411. Magnesia is essential to fertility in a soil; but there 
are very few lands which are not already supplied with an 
abundance of it for meeting the demands of the growing 
plant. In a few soils where it is deficient, it may be supplied 
with advantage in connection with lime. Limestones fre- 
quently contain a large per centum of carbonate of magnesia, 
which is reduced to caustic magnesia, just as the carbonate 
of lime is reduced to caustic lime, in the process of burning. 
This mixture of magnesia and lime must be applied more 
lightly than simple lime, because large quantities of caustic 
magnesia are injurious to the soil. 

Magnesia will not serve, so well as lime, the various 
secondary purposes of " sweetening sour soils," of " decom- 
posing organic and mineral compounds," etc. It is some- 
times applied in the form o^ pliosjpliate or sulphate; but the 
beneficial results from these are generally to be attributed 
more to the influence of the phosphoric and sulphuric acids, 
than the magnesia with which they are combined. 

ASHES. 

412. Ashes, consisting of the mineral matter derived from 
the soil by plants, might be esjDCcted to form one of the best 
fertilizers to be found; and such is really the case. The 
mineral bases, as they are found in ashes, are not in the same 
combinations which they have in the plant. Those which in 
the plant were combined with difi'erent organic acids, become 
carbonates by burning. Some others, too, such as the phos- 
phates, may be considerably modified by the heat during 
combustion. But they are still in a favorable condition to 
afibrd nourishment to new plants. 

413. The ashes used for fertilizing purposes are derived 
chiefly from the fuel consumed in our dwellings, and in the 
mechanic arts. Near the sea-coast, farmers often avail them- 
selves of the rich mineral manure which may be procured 



244 ASHES. 

by burning- sea-weeds. These are gathered, dried, and then 
burnt in shallow pits, which prevent the ashes from being 
blown about by the wind. Soda and chlorine, obtained from 
sea-water, are among the most abundant constituents of these 
ashes. They were formerly employed largely, as a source 
from which soda was prepared; but better and cheaper 
methods are now adopted (§ 96). 

414. The average quantity of ashes produced by the vari- 
ous kinds of wood commonly used for fuel, is about 3 pounds 
from 100 pounds of well-dried wood. Where much pine is 
used, this average is too great, since pine yields only about 
07ie per cent of ashes. The quantity from sea-weeds varies 
to some extent with the different varieties of plant ; but we 
may take seventeen per cent as about the average, which 
shows that these plants are very rich in mineral matter. 

415. The following table gives a general view of the value 
of ashes, as determined by their constituents. The Jirst 
column gives the composition of those obtained by burning 
a mixed fuel, consisting of about one-half oak, and the re- 
mainder beech, ash, hickory, and maple in about equal pro- 
portions. The second column gives the composition of the 
ashes of sea-weeds. 

TABLE VII. 

3000 Pounds of Dry Wood give 100 Pounds Mixed Wood Sea Weed 

of Ashes, containing Ashes. Ashes. 

Potassa 9.3 lbs. 17.4 lbs. 

Soda 2.5 " 27.1 " 

Lime 41.2 " 7.2 " 

Magnesia G.2 " 8.0 " 

0.^ides of Iron and Manganese 1.6 " 0.1 " 

Sulphuric Acid 1.5 '• 17.0 '« 

Phosplioric Acid 4.3 " 3.0 " 

Silica 3.2 " 1.3 " 

Carbonic Acid 30.7 " Omitted. 

Chlorine 0.5 " 18.2 lbs. 

Iodine 0.7 " 



ASHES. 245 

When we compare the above table with Table III, which 
gives us the mineral constituents of various crops, we find 
ashes rich in those substances most largely demanded by 
plants ; and when we refer to Table V, we see that these 
substances are not always abundant in the soil. The bases — 
that is, the potassa, soda, lime, etc. — are chiefly found as 
carbonates in ashes, while smaller portions of them are com- 
bined with th-e phosphoric, sulphuric, and silicic acids. The 
chlorine is most probably combined with sodium. The salts 
of potassa and soda being soluble, are more apt to be lost by 
exposure to rain than are the salts of lime and magnesia. 
Some of the silica in ashes is in combination with potassa, 
and in a soluble condition. This soluble silica, for most soils, 
is one of the most valuable fertilizers which can be em- 
ployed. We have already learned that its presence is neces- 
sary to the full and healthful growth of the stalks of plants ; 
and its influence may be frequently seen on the clean, strong 
and healthy straw of wheat growing upon soils recently 
dressed with ashes. The effects of ashes upon grass and 
corn crops are almost always highly favorable. 

41G. Ashes. are caustic in their character, from the pre- 
sence of carbonates of potassa and soda. They also contain 
a large per cent of carbonate of lime. These qualities make 
them a most appropriate manure for sweetening sour soils, 
such as those which have been recently drained. They 
serve a good purpose, too, in hastening the decay of organic 
matter in compost heaps. But newly-burnt ashes should not 
be mixed with guano, and other manures containing ammo- 
nia, because there is generally caustic lime enough produced 
by the fire, to set free considerable quantities of ammonia. 
After ashes have been exposed for some time to the air, 
however, the caustic lime becomes a carbonate, and these 
effects will not then be produced by it. 

417. Leached ashes are much inferior to the unleachcd in 
21* 



246 ASHES. 

their fertilizing value, a large quantity of the soluble matter 
having been carried oflf in the lye ; but still they are valuable 
on account of having some potassa and soda left in them, 
and from the large quantity of lime they have retained, to- 
gether with most of the phosphoric and some of the sulphuric 
acid and silica. They should be applied much more largely 
than unleached ashes, to produce a like effect. 

418. The soap-suds used about the farm-house, contain not 
only the soluble matter taken out of the leached ashes in 
making lye, but also a considerable quantity of valuable 
animal matter employed in making soap. If these were care- 
fully preserved, and thrown upon a compost-heap, which 
would absorb them, they would be found to reward the labor 
bestowed, in adding their fertilizing value to the soil. A 
sheltered compost-heap, formed of wood-yard scrapings, turf, 
weeds, and enough of vegetable mould to prevent the suds 
from passing through the mass too quickly, should be con- 
structed near every wash-house, with a trough leading to it, 
to convey all the spent suds to the top of it. 

Coal-ashes should not be neglected. They consist, it is 
true, chiefly of alumina and silica, and, in some varieties, 
lime is abundant ; but all of them contain enough of the salts 
of potassa and soda, and of sulphates and phosphates, to 
make them well worth the trouble of applying them to the 
soil when near at hand. 

419. Ashes and Plaster. — These make a favorite mixture 
with many of our best farmers. They are applied with great 
success to corn, by being dropped with it in the hill, or being 
sprinkled over it soon after it comes up. Some prefer sowing 
the mixture broadcast before planting, so that the rains may 
carry it down into all parts of the soil, where it will be found 
by the roots as they spread out during the growth of the 
crop. The gypsum thus spread out is supposed, too, to be 
in a more favorable condition for combining with ammonia 



SALTS OF SODA. 247 

from the air and the soil. Sown upon clover fields and 
meadows, this mixture has sometimes a remarkable effect, 
and is, in almost every case, beneficial. It contains the ele- 
ments of fertility most largely demanded by grass crops. 
Lime, potassa, sulphuric, and phosphoric acids, and espe- 
cially soluble silica, are all taken up freely by the grasses. 

A special advantage arises from mixing ashes with plaster, 
when the mixture is to be applied to a soil in which sul- 
phuric acid is very deficient. The ashes, or rather the car- 
bonate of potassa in the ashes, so acts upon the sulphate of 
lime, that mutual decomposition takes place if the mixture 
is in a moist condition. The lime and potassa exchange 
places, so that we have carbonate of lime instead of carbonate 
of potassa, and sulphate of potassa instead of sulphate of 
lime. This change goes on with considerable rapidity, if the 
mingling of the two manures is complete, and the mass is 
kept moist and warm. 

The sulphate of potassa is much more soluble than the 
plaster, and is, hence, diffused through the soil at once by 
the rains, and made immediately available by the roots of 
the plant. . 

SALTS OF SODA. 

420. Common salt is a very valuable fertilizer for many 
crops, but especially for those requiring considerable quan- 
tities of chlorine. Mixed with ashes and plaster, it has 
proved highly beneficial to crops of potatoes, hay, and corn. 
Four bushels of unleached ashes, and one bushel of plaster, 
with a gallon of salt, make a most valuable preparation for 
potatoes or grass. I have found twelve bushels of this mix- 
ture to bo suSicient for an acre of potatoes planted in the 
ordinary way. Grass lands would require a greater or less 
quantity, accoi'ding to the nature of the soil. Every farmer 
should make experiments for himself Asparagus beds re- 



248 NITRATES BURNT CLAY. 

quire abundant and frequent applications of salt. The most 
convenient way to apply it is to dissolve the salt in water, 
and sprinkle the solution over the bed with a common water- 
sprinkler. 

421. Sulphate of soda is now a very cheap article, being 
produced in large quantities in the manufacture of muriatic 
acid (§ 80). It has been advantageously used as a fertilizer. 
This substance, as well as common salt, may be beneficially 
mixed with other fertilizers. 

422. Silicate of soda is easily prepared by fusing sand and 
carbonate of soda together. If two parts of carbonate of 
soda are fused with one part of sand, and a little powdered 
charcoal, the mass is soluble in water. The solution has 
been applied to wheat with very marked benefit. Soluble 
silica is so much needed on many soils, that it is to be hoped 
that means will be devised for preparing it at a moderate 
cost. 

N ITRATE S. 

423. Nitric acid is one of the sources from which plants 
obtain nitrogen ; hence, the nitrates have proved to be valu- 
able as manures. The nitrates of potassa and soda have 
both been used with great success. Dilute solutions of these 
salts may be sprinkled upon the soil ; or, if sprinkled over 
compost-heaps, they find their way to the soil in mixture 
with other manures. 

BURNT CLAY. 

424. Burning sometimes has a very remarkable influence 
in making a soil more productive. There are several causes 
which probably combine to produce this effect. (1) A part 
of the organic matter mingled with the soil is reduced to 
ashes, and thus made at once effective in providing its mine- 
ral matter in a free form to nourish the next crop. (2) Part 
of the organic matter is only charred, and left as finely 



RUNNING WATER A FERTILIZER. 249 

divided carbon in tlie pores of the soil, where it serves as a 
valuable absorbent of ammonia, carbonic acid, and water. 
(8) The mineral matter already in the s(fil is frequently im- 
proved by heat. Some substances, such as protoxide of iron, 
are more highly oxidized; and others are disintegrated, and 
rendered more soluble. (4) The mechanical condition is 
often improved by the soil being made more loose and 
porous. 

RUNNING WATER A FERTILIZER. 

425. The water of springs and streams is never pure. It 
contains, as has been stated (§ 61), both mineral and organic 
matter of the proper kind, and in the proper condition to 
nourish a growing crop, or to add fertility to the soil through 
which it passes. The fertilizing matter is conveyed by the 
water partly in solution, and partly in minute particles, which 
are mechanically transported and left upon the surface. In 
sections of country where the land is rolling, and running 
streams are numerous, a portion of every farm, through 
which one of these streams passes, can be not only watered, 
but enriched by watering, if properly managed. 

The purest spring-water has always portions of mineral 
matter from the soil and rocks through which it has passed. 
Decaying organic substances in the soil yield ammonia, which 
is also found, in some form of combination, in almost all 
springs. In streams which have received the water from 
the sewers of towns and cities, ammonia exists in verj' con- 
siderable quantities, and so do soluble and insoluble mineral 
ingredients. A careful farmer, although he may have no 
town or city above him to send down to his meadows, water 
freighted with fertility, will generally find that he has some 
careless neighbors up-stream, who will let him have the 
benefit of the "wash" from their barn-yards, hog-pens, and 
other like places j and not complain of his turning it into 



250 R I" N N 1 N O WATER A FERTILIZER. 

hay aud grain, instead of lotting it run on to the ocean, to 
be forever lost. 

420. Aj)2ili(:athn. — Running water can, of course, be ap 
plied only to those portions of land which are lower than the 
point where the water is turned out from the streaiu. By 
means of ditches conducted along the hill-sides, with just 
foil enough to give the necessary motion to the water, many 
acres of a farm may often be completely irrig-ated. In order 
to accomplish this thoroughly, with as little waste of water 
as possible, some attention must be given to the coustructiou 
aud arnuigemeut of the ditches. The principal ditch, or 
conductor (*l, A, Fig. 47), should wind around the hills 
nearly upon a level, so as to carry the water along the high- 
est possible line. Openings, from 10 to 20 feet apart, must 
be made, as at a, a, a, to let out small streams from the main 
conductor. Small shallow channels should lead off from these 
openings to the right and left, nearly parallel with the main 
conductor; for the purpose, in the fii-st place, of properly 
diffusing the water; and, in the second place, to prevent the 
little stream from cutting for itself a channel deeper than is 
wanted. These are seen at ?>, b, h. If the space to be 
watered extends far below the main ditch, other smaller 
ditches, as ^, B, C, C, and i>. D, should be run parallel with 
A, A, and at distances varying from 30 to 50 yards. These 
may vary in size as they are more or less distant from ^1. ..4, 
because a portion of the water conveyed by -4, ^4 will be ab- 
sorbed by the soil before it reaches B, B ; and when it reaches 
C\ G, the quantity is still less. Then, these secondary con- 
ductors are not designed so much to convci/ water from one 
part of the meadow or field to another, as they are to redis- 
tribute what has run down from ^1, J^. Finally, if there is 
not a natural channel at the base of the hill, as E, E, to carry 
off the surplus water, an artificial one should be dug for that 
purpose. 



RUNNJNO VVATLR A FKKTILIZER. 251 

Fig. 47. 




2r)2 RUNNING WATER A FERTILIZER. 

427. The kind of soil most suitable for irrigation is one 
with a porous sub-soil. The water can then penetrate to a 
greater depth, and surplus water can escape as it does in a 
drained soil. If the sub-soil is an impervious clay, a system 
of covered drains should be constructed beneath the surface 
before the ditches are made ; or, if this cannot be done, and 
the land is to be kept in grass, it should be cultivated to the 
greatest possible depth with the sub-soil plow, before the 
grass is sown. When the soil is thus rendered porous, one 
portion of it may be completely saturated with water, and 
the stream then be turned upon another, while the former is 
left free to be acted upon by the air. By alternating in this 
way, a small stream may be made to water a large surface. 
If the land is under cultivation with corn, it may be watered, 
when necessary, by the same system ; but the water should 
be turned out upon the soil less frec^uently, in this case, than 
in the case of a grass crop. 

428. Effects. — The prcaent crop is provided by the stream 
of water : (1) With an abundant supply of moisture, which 
is of great importance, and the land is thus made indepen- 
dent of drought;* (2) With mineral and organic manure al- 
ready in solution. Subsequent crops are, moreover, benefited 
by surplus fertility left in the soil by the water, and by de- 
caying roots, stalks, and blades, of which some portions 
always remain after every crop that has been removed. After 
a hay-crop has been removed, the meadow should be watered, 
in such a way as not to allow the water to pass off through 
the soil, or to run freely over the surface ; for, in that case, 
it will carry off fertilizing matter, which had better be re- 
tained. To prevent this, the quantity must be so regulated 
that all, or nearly all, will be absorbed, and afterwards eva- 
porated from the surface, or thoroughly filtered before it runs 
off from the field ; thus the fertilizing substances will be left 
in the soil. But if the water contains a considerable quan- 



QUESTIONS. 253 

tity of organic and sedimentary substances, it should be 
allowed to pass freely and abundantly over the surface. 



QUESTIONS ON CHAPTER XV. 

§§ 379 — 382. AVhat is said of Stable Manure? How must the urine 
be preserved? First method given ? Second? AVhat else must be 
done besides rendering ammonia involatile ? If manures cannot be 
put into sheds, what should be done with them ? What of the urine 
of cows, sheep, and hogs? Of their solid excrements? Is human 
excrement valuable ? How does it compare with that of other ani- 
mals ? Is much of it wasted ? What arrangements may be made 
for its preservation ? 

383 — 391. What is Guano? Why so rich in fertilizing matter? 
Its most abundant and most valuable ingredients? Where is the 
best guano found ? Analogy between these deposits and those of 
coal ? What of the African, Chilian, and Mexican guanos ? What 
does Table VI represent? With what is the ammonia of guano com- 
bined ? How do they become volatile? Why is the application of 
guano important? AVhat three things are required in its economical 
use? AVhat quantity is to be applied? Advantage of mixing with 
other manures? Most common method of applying it? AVhen 
should it be diluted? First thing (o) to be done in preparing guano? 
How mixed with humus (b)t Use of sulphuric acid (c)? AVhat 
effect does the acid produce ? AVhy always to be thoroughly min- 
gled with the soil {d) 1 AVhat do some farmers think of the exhaust- 
ing effects of guano? Does it really exhaust a soil? AVhy not? 
May its use exhaust some elements? Illustrate. AVhat cases men- 
tioned ? How prevented ? Best method of using guano for perma- 
nent improvement? How does it act when applied to green crops to 
be plowed down? AVhat precautions necessary in buying? How 
tested ? Domestic guano ? 

392 — 396. AVhere are anfniaZ substances collected? AVhat gives 
them agricultural value? How preserved? AVhat offish? Insects? 
AVhat gives value to Bones ? How do they compare with guano ? 
Why is their influence slow ? How does sulphuric acid render bones 
more energetic ? How is the acid used ? 

397,398. Is i/2ne?ai J/a«i«e important ? AVhy? Illustrate. AVhat 
indirect influence does it often produce ? 
22 



254 QUESTIONS. 

399 — 410. Why must Lime exist in every soil ? In what condition 
must it be? (a) In what condition should caustic lime be applied? 
How much? On drained swamps? Why? First eifect of caustic 
lime? Second? Third? Fourth? Cautions? {b) What is mild 
lime? Experiment? Its effects? (c) Phosphate of lime obtained? 
What does it supply? Has it an immediate effect? lioyt la super- 
phosphate of lime prepared ? What is manipulated guano ? Bone 
black ? [d) What does Gypsum provide for crops ? Effects ? To 
what crops is it especially applicable? AVhy ? (e) How is the term 
marl, used? What is shell-marl? Marls of the tertiary strata? (/) 
Why is silicate of lime important? Explain its action. 

411. Is J/aywfsia valuable in soil? Why? Is it valued as a fer- 
tilizer? AVhy not? Will it not take the place of lime? What salts 
of magnesia are sometimes applied to land ? 

412 — 418. Why might we expect Ashes to form a good fertilizer? 
Are their constituents modified in burning ? Chief source of ashes? 
On the sea-coast? Average quantity produced by wood? What 
does Table VII represent? What do we learn by comparing it with 
Tables III and V? What portions of ashes are most readily lost by 
exposure? Why suited for "sour soils"? Influence on organic 
matter? Value of leached ashes? Value of soap-suds? Why? 
How collected ? Coal ashes ? 

419. 'Row are plaster and ashes used together? Modes of apply- 
ing them ? Why especially adapted to clover and grasses ? What 
chemical changes do they produce on each other ? 

420 — 424. What fiocTo! compound is first mentioned? What does 
common salt furnish to crops ? On what crops is it most beneficial ? 
What is said of sulphate of soda ? How is silicate of soda prepared ? 
What gives the Nitrates their value ? Influence of burnt clay ? First 
cause of this? Second? Third? Fourth? 

425 — 428. Is rnnni7ig water ever pure ? What substances are 
found in it? How does it fertilize a soil? Where do springs get 
their mineral and organic matter ? How is the water of streams 
furnished with fertilizing substances ? To what lands can this water 
be applied? Describe the ditching in Fig. 47. 'What kind of soil is 
best suited for irrigation? How should clay soils be prepared? 
How may a small stream be made to water a large surface ? 



APPLICATION OF FERTILIZERS. 255 



CHAPTER XVI. 

APPLICATION OF FERTILIZ E RS — PLANTING AND 
CULTURE OF CROPS. 

429. It may be well to sum up, in review, some of the 
general principles and rules to be observed in applying fer- 
tilizers to the soil. 

(a) Manures may be applied either in a liquid or solid 
form. The liquid form has the advantage of producing the 
most speedy effects, thus returning its profits most quickly to 
the pocket of the farmer; but, in this country, liquid ma- 
nures are not much used, except on gardens and small lots. 
In older countries than ours, in some parts of our older 
States, in the vicinity of cities, and in all places where land 
is costly, and where a convenient and high market brings a 
prompt return for manure and labor, the liquid fertilizers are 
found frequently very economical. The manures of the 
solid form are most commonly applied, and have the advan- 
tages, generally, of requiring less trouble in their prepara- 
tion and application, of affording a much greater variety of 
ingredients, and of being much more durable; and hence, 
requiring less frequent application. 

(h) Solid manures should be as well pulverized as possible, 
so that they may be thoroughly mingled with and diffused 
through the soil. In this condition, a smaller quantity 
serves for a single application ; and the farmer gets back 
again, in a shorter time, the capital and labor invested in the 
manure and the land. 

(c) Manures of every kind should be as thoroughly incor- 



25G ATPLICATION OF FERTILIZERS. 

porated with the soil as possible, so that the roots of the 
crop may find some portions wherever they run. If a ma- 
nure is heavy, like lime or plaster, it is best to apply it on 
the surface after the land has been broken up. It may then 
be stirred into the soil, and, by its weight, it will gradually 
sink towards the bottom during the cultivation. Soluble 
ingredients, such as the alkaline salts in ashes, will soon be 
carried down into the earth by rain-water, even when they are 
applied only on the surface. 

(fZ) Fermented manures have their ammonia already in a 
volatile form ; and unless they have been composted with 
other substances, much of the ammonia will escape, by 
exposure on the surface. Hence they should be speedily 
covered or mingled with the soil. The tendency of all vola- 
tile matter is towards the surface. Especially is this the 
case in porous soils ; hence guano, and other forms of manure 
which have passed through the process of fermentation, are 
frequently most effective and most durable in their influence 
when plowed down. 

(e) The crop should find the required fertilizers present in 
the soil, and in the proper condition to be absorbed, as soon 
as the roots are sufficiently developed to take them up as 
food. Organic food is required at every period of the plant's 
growth, and should therefore be present at the time of plant- 
ing. Of the mineral ingredients, silica and lime are taken 
up most abundantly during the growth of the stalk, while 
potassa and the phosphates enter most abundantly into the 
grain ; but in both cases it is best to apply the fertilizers, 
either at or before the time of planting. Important chemi- 
cal changes are often necessary, before a manure becomes fit 
for plant food. Bone dust, for example, has frequently, 
perhaps generally, a more decided effect upon a wheat crop, 
the second or third season after its application, than it has 
during the first. It doubtless undergoes, in process of time, 



APPLICATION OP FERTILIZERS. 257 

changes in the soil, either from having a portion of its lime 
abstracted by lime-feeding plants, or under the influence of 
other substances, by which it is reduced to a more soluble, 
and hence more available condition. Unfermented manures 
applied to corn, or to a clover sod to be fallowed for wheat, 
generally have a better eflFect upon the succeeding wheat 
crop, than when applied directly to it at the time of sowing. 
430. Top-dressivg is more extensively practised now than 
it was formerly; but, like all other modes of application, it 
must be resorted to only under certain circumstances. There 
is no mode which can ever be universal in its applications ; 
and where we find one particular method very successful in 
two or three experiments, there is always danger of some one 
drawing the general conclusion that this is, finally, to be the 
only method of operating. Top-dressing is doubtless favor- 
able to grass and clover crops in the Winter and Spring 
Organic manures thus applied have their soluble ingredients 
carried down by the rain into the soil, where the roots will 
find them at the very beginning of their Spring growth. 
The unrotted portions of manure, remaining upon the sur- 
face, are soon covered by the leaves and stalks that spring 
up through them, and decaying, form a rich, warm mould 
about the roots. Top-dressing for corn will do well, if it be 
done with the newly-collected manures from the stables and 
barn-yards during the Winter. The urine, and other por- 
tions soluble by the Winter and Spring rains, are carried 
down, and become very thoroughly incorporated with the 
soil ; while the remaining portions are turned down after- 
wards by the plow, and are gradually converted chiefly into 
humus. Manures may always be applied to the surface 
during the Autumn or Winter without serious loss, and fre- 
quently with decided advantage. It is always better to have 
stable and yard manures exposed to rains itj)on the field, than 
around the ham. 
22* 



258 PLANTING. 

431. Mixing AND Composting Manures. — When the 
farmer wishes to have a great variety of fertilizing ingre- 
dients provided for his crop, and applied at the same time, 
he may mix several kinds of manure together; but, in doing 
this, he must weigh carefully all the advantages and disad- 
vantages involved. 

Besides giving a variety of food to the crop, some of the 
most obvious advantages arising from mixing manures, are : 
(1) That one may render another involatile, of which we 
have examples in the effect of humus or gypsum in " fixing 
ammonia;" and (2) That one may make another more 
soluble, as in the case of sulphuric acid poured upon bone- 
dust. 

432. Corresponding disadvantages are seen : (1) In a 
volatile substance, especially ammonia, being expelled by 
another, such as caustic lime; and (2) In the addition of 
something which may make valuable ingredients, already 
present, more insoluble. Sulphate of iron (copperas), for 
instance, added to manure containing phosphate of potassa 
or phosphate of ammonia, will produce the very insoluble 
phosphate of iron ; thus rendering the phosphoric acid much 
less soluble than it was in its former combination. But it 
will only require a little reflection to avoid these difficulties. 

PLANTING. 

433. The general principles have been given which should 
govern the farmer in both the mechanical and chemical 
preparation of the soil. By plowing and draining, it ig 
opened up, and ready to be acted i\Y>on by air and moisture, 
to receive such chemical appliances as will improve its com- 
position, and also to be penetrated by the roots of cultivated 
crops. By appropriate manure, it is supplied with an abun- 
dance of all the food wanted for the nourishment of these 
crops. 



PLANTING. 259 

When the ground is thus made ready, the next object of 
attention, before we bring the seed and the soil together, is 
to know that we have seed of the best kind and quaUty. 

434. Selection of Seed. — This is a matter of the 
highest importance to good farming. "As a man soweth, so 
shall he reap," is one of the sacred proverbs, no less true in 
the physical than in the moral world. The farmer is apt to 
reap, not only the same kind, but also the same quality, as 
that which he has sown. A little shrivelled grain, with a 
poorly-developed embryo, will generally send up a weak and 
sickly stalk, able to bear only such grains as that from which 
it sprung; while, on the other hand, the vigorous germ, found 
in the full, plump grain, forms at once a strong foundation 
for a healthful future growth. 

435. If the farmer has seed of the right hind, he may, 
with a little care and trouble, improve its quality very con- 
siderably in a few years. In wheat, the first portions that 
ripen are usually the best. These should be first cleared of 
rye, cockle, and other foreign plants ; then cut as soon as 
ripe, and kept apart from the general crop, for seed. If 
this process is repeated for several years, the effect will be 
seen in the improved quality, and earlier ripening of the 
wheat. 

Seed corn should be selected in the field. The largest 
ears, from those stalks which bear two ears, are believed by 
many of our best farmers to be most desirable for ,seed, be- 
cause they are thought to be most likely to yield twin-bearing 
stalks for the next crop. There is good reason for this 
belief, from the fact that the ordinary varieties of Indian 
corn, when well cultivated on good soil, and not too much 
crowded for full development, generally yield at least two 
ears from every stalk; and, where only an occasional stalk 
has an opportunity of attaining its fullest growth, this is 
indicated by the production of two ears. In selecting the 



200 PLANTING. 

best ears, then, from such stalks, we have the product of 
the most vigorous and full growth in the crop. Those who 
have tried this method of selecting their seed, testify that 
the number of double-eared stalks can thus be greatly mul- 
tiplied in a few years. It is a subject worthy of further 
careful experiment. 

Every one who has not the proper kind of seed on his 
farm should at once make a change, even if he should be 
compelled to pay what he may regard as a very high price 
for seed of good quality. Changes of wheat and other 
grains, from one soil to another of different character, and 
from one climate to another, seem in many cases to prove 
beneficial. Wheat from the shores of the Mediterranean, 
and even from Central and Northern Europe, is generally more 
free from disease, and often escapes the ravages of insects 
more entirely, than the varieties which have been long culti- 
vated in our own country. Grains transported from latitudes 
in which the season is short, to those in which it is much 
longer, ripen early, at least for a few seasons; but they finally 
appear to adapt their period of growth and maturity to the 
new climate. Our Government, through the agency of the 
Patent Office, is doing our agriculturists good service, by 
giving them an opportunity of trying various kinds of seeds 
from all parts of the world. 

436. In determining the variety of wheat or corn to be 
planted, two circumstances should have their influence. (1) 
The productiveness of different varieties should be, as far as 
possible, ascertained. The difierent kinds of wheat and 
corn often vary in their relative products per acre, so much 
as to make this an important point of attention. The labor 
of cultivating an acre of land in a variety of corn which 
yields 80 bushels, is no gi'eater than that of cultivating the 
same quantity of land in another variety which yields only 
50 or 60 bushels ; and the same is true of wheat, or any 



PLANTING. 2G1 

other grain. (2) The difference in the marJcet valve per 
bushel must not be disregarded. Twenty bushels of white 
wheat, at $1.25, are equal in value to twenty -five bushels of 
red wheat, at $1.00. The mitritive value of corn to be used 
in feeding farm stock, should be estimated, in selecting the 
kind to be planted. Yellow corn is regarded by stock-raisers 
as superior to the white, in its fattening properties. For 
bread, the white variety, with a clear, flinty grain, is most 
highly esteemed. 

437. The oat grain {Avena Stafiva') degenerates, to some 
extent, in the Southern States, after a few years' cultivation. 
The stalk may still grow with all the luxuriance desired, but 
the grain gradually becomes less full and heavy. For this 
reason, Southern farmers who wish to cultivate oats, should 
frequently (at least once in four or five years) renew their 
seed by importation from a more northern latitude. 

438. Preparation of Seed for Planting. — All kinds of 
seeds should be tlioronghhj clear of everything which can 
spring up and grow at the same time with the cultivated 
crop. Indian corn is easily separated from every other kind 
of seed, by the peculiar manner of gathering it; but not so 
with wheat. Everything that grows with wheat must be 
gathered with it; and everything that ripens about the same 
time, will be still represented by its seeds, when the grain is 
threshed. Hence the great difficulty of keeping seed-wheat 
clean. Spring wheat is liable to become polluted with oats, 
because it has the same season of growth, while oats sown 
with winter wheat are killed by frosts. Winter wheat is 
most apt to have rye, cockle, and cheat (chess) mixed with 
it, as these, like the wheat, arc biennial, and ripen simulta- 
neously with it. 

439. In order to estimate properly the importance of hav- 
ing clean seed, it must be remembered that these foreign 
grains do not simply injure the quality of the flour produced 



2G2 PLANTING. 

from the crop, but they also diminish the quantity of the 
grain, just to the extent of their own presence. This may 
not be entirely true of oats and rye, for they are not entirely 
worthless ; but of cockle and cheat it certainly is true ; for 
the same ground which produced a stalk of either of these 
plants, would have produced a stalk of wheat, if wheat had 
been sown in their stead. 

A few bushels of wheat may be carefully picked out, head 
by head, and sown on a piece of clean and good soil ; and a 
supply of clean seed, sufficient for the whole of the next 
sowing, be thus obtained. 

440. Steeping Seed-Grain. — A more prompt and vigor- 
ous germination, and a more rapid early growth, may be 
brought about, in almost all kinds of grain, by steeping the 
seed in suitable solutions. If the soil is then good, the early 
growth, thus urged forward, will continue ; but steeping the 
seed in a solution of one substance, can never make up de- 
ficiency in other elements of fertility in the soil ; nor can it 
compensate for defective ploicing, or negligence in other 
modes of tillage. 

The solutions used for steeping sometimes have the effect 
of destroying the eggs of insects, and the germs of injurious 
fungi, such as smut. Or, if these are not destroyed, their 
influence may be, to a great extent, counteracted by the in- 
creased vigor given to the young plant by the fertilizing salts 
in which the grain has been soaked. 

441. Several salts may be used in the same solution, so as 
to give a variety of such food as the plant may require. The 
salts most frequently employed for this purpose are those 
containing potassa, soda, and ammonia, combined with such 
acids as are wholesome for plants. The ammonia salts, like 
the ammoniferous manures, are generally more powerful in 
their influence than the salts of the other bases. The sul- 
phate of ammonia and sal-ammoniac arc the cheapest salts 



PLANTING. 2G3 

of that class ; but urine may be used with like effects, on 
account of its ammonia, and at much less cost. Nitrate of 
potassa (saltpetre), nitrates and sulphates of soda and mag- 
nesia, phosphate of soda, and common salt, may all be em- 
ployed in the preparation of steeping liquids. Some of these 
are within the reach of every farmer, and may be used at a 
trifling cost. The collection of urine requires only a little 
management, while saltpetre and common salt are found in 
every wayside store throughout the whole country. 

442. The following receipts may be useful as general 
guides in preparing solutions. They are suitable for any of 
the cereal grains. 

a. For every bushel of wheat or corn, take 45 gallons of 
water, and dissolve in it one pound of saltpetre and one pound 
of common salt.* Pour the solution upon the grain in a 
tight vessel, and set it aside in a warm place to soak for 24 
or 36 hours. Then drain off the surplus water (preserving- 
it), and mix with the grain, while wet, as much plaster as 
will adhere to it, or, rather, as much as will keep the grains 
from adhering to one another in planting. About half-a- 
bushel of plaster is sufficient for a bushel of grain. Caustic 
lime, used in the same way, is believed to prevent smut. 
The water may be used a second time, for about half as 
much grain, by dissolving a little more saltpetre and salt 
in it. 

h. A better solution than the preceding is formed by dis- 
solving, in 4^ gallons of water, for each bushel of grain to 
be soaked, -^ lb. sulphate of ammonia, ^ lb. saltpetre, ^ lb. 
Epsom salts, and \ lb. common saltj and, if phosphate of 
soda can be obtained, add \ lb. of it. Soak the grain and 
mix with plaster, as in the first receipt. 

* A strong brine of salt tends to retard germination, by preventing 
decay in the albumen. 



2Gi PLANTING. 

c. To 4 5 gallons of urine, add a half-pint of sulphuric 
acid (oil of vitriol), J lb. saltpetre, I lb. Epsom salts, 2 lb. 
common salt. The solution is to be used as before directed. 
In this case the sulphuric acid unites with the ammonia of 
the urine, and forms sulphate of ammonia. This solution is 
improved by standing a day or two before it is used. 

Other solutions may be used, as the convenience or che- 
mical knowledge of the farmer may suggest. A strong de- 
coction of manure, formed by passing water through a barrel 
or box compactly filled with Iresh stable-dung, or that col- 
lected from hen-roosts, with the addition of a little sulphuric 
acid, nitre, and salt to the liquid, after it has passed off, will 
give a solution closely resembling the one last mentioned (c). 

When the quantity of grain to be prepared at one time is 
large, it may be more convenient to use a smaller amount of 
liquid, and apply it in a different way. The following plan 
will be found convenient; For every bushel of wheat provide 
I2 gallons of water, and in this dissolve the salts as above 
given. Spread the grain upon a close floor, to the depth of 
5 or 6 inches, and with a common water-sprinkler apply about 
one-third of the solution. Let it stand two or three hours, 
stirring the mass occasionally. The grain will in the mean- 
time have absoi"bed most of the moisture ; then sprinkle 
over it another third of the solution, and let it stand 24 or 
3G hours. Just before it is to be sown, let the remaining 
third of the solution be applied ; and while the grain is still 
wet, mix it with plaster or caustic lime, or any fertilizer you 
may wish to sow with it. If no pulverized fertilizer is to be 
used, all the liquid should be applied as soon as the grain 
can absorb it, so that it may stand at least 24 hours after 
the last portion has been applied. The grains will then be 
sufficiently dry upon the surface to prevent their adhering 
to each other in sowing. 

444. Time of Planting. — This must vjiry widely, even 



PLANTING. 265 

for the Fame crop, under variations of climate ; and also, to 
some extent, with variations of soil and exposure, even in 
the same climate. It is, therefore, difficult to lay down any 
rules, except those of the most general character. Crops 
planted in Autumn, such as wheat and rye, should have time 
to form a good strong root, before Winter sets in. The ex- 
perience of the most successful farmers in any particular 
section of country, is the best guide for the young farmer, 
at least until his own experiments have been tried sufficiently 
often to result in experience. 

Cold, clay soils, and those having a northern exposure, 
require earlier sowing than such as are warmer, from their 
composition or southern exposure; for the Fall growing 
season is shorter in the former than it is in the latter case. 

445. In the Spring, oats and Spring-wheat crops may be 
sown as early as the ground can be conveniently prepared. 
This will give the force of hands and horses an opportunity 
of making preparation for planting other crops, especially 
corn, which always demands thorough cleaning and breaking 
up of the soil, in order to secure a good crop. Corn should 
be planted late enough to escape the frosts of Spring. It is 
a crop which requires much light and heat to cause a rapid 
growth, and will, therefore, make no great progress so Ion"- 
as the days are short and cool. Hence, we find in the lati- 
tude of Virginia that corn, planted about the first of April, 
has grown very little more by the last of June, than that 
which was not planted till the first of May. The planting 
season for corn has, then, a tolerably wide range. Good 
crops are made from plantings ranging over the whole period 
between the first of April and the middle of May. Farther 
south the planting period is still longer. 

446. The chief advantages of early planting for corn are, 
in the first place, that, in tobacco-growing regions, tlie 
''working" (tending) of the corn, may be as fiir advanced as 

23 



2GG QUESTIONS. 

possible before the planting of the tobacco crop requires 
attention ; and, in the second place, in wheat-growing regions, 
that the tending of the corn crop may be pretty well com- 
pleted before wheat harvest begins. 

447. For jpf^tatoes there are two favorable seasons for 
planting. The first, very early in the Spring; the second, 
late in June, or, in more southern latitudes, the first of July. 
The potato is not capable of bearing very hot weather while 
at its highest stage of growth. The weather, at that time, 
should be moist and mild. When potatoes are planted about 
the last of March or first of April, the tubers are formed 
chiefly during the month of June; and, although this is a 
warm month, the ground has not become so hot, nor usually 
so dry, as it is in July. Hence, they are tolerably well ma- 
tured before the scorching weather of midsummer sets in. 
If they are planted in the early part of summer, they come 
up and pass through the stage of growth proper for cultiva- 
tion, by the time the very hottest weather has passed. Then, 
if they get good rains during the latter part of August and 
early part of September, fine tubers are formed, and a fair 
crop is realized. 

QUESTIONS ON CHAPTER XVI. 

§ 429. In wliat two forms may manures be applied (a) ? A Jvan- 
tage of the liquid form ? Which form is most common ? (i) How 
should solid manui'es be prepared? Why? (c) Why should manures 
be perfectly incorporated with the soil? How accomplished? [d) 
Should fermented manures be exposed? Tendency of all volatile 
matter? (e) How should the crop find the fertilizers in the soil? 
When are silica and lime taken up most abundantly? What are 
potassa and the phosphates? Is time required for some manures? 
Illustrate. 

430. AVhat of top-dressing ? Can any mode be imiversally employed ? 
To what crops and what seasons is top-dressing especially suited ? 
Why? Why are the Fall and Winter suitable for applying organic 



QUESTIONS. 267 

431, 432. How may great variety be obtained in a manure? Other 
advantages of mixing? The first? The second? First disadvan- 
tage ? Second ? 

433. Means used for reducing the soil to its proper mechanical 
condition? How is its chemical condition improved? When the 
ground has been prepared, what is the next step ? 

434, 435. Why is the selection of seed important? Effect of plant- 
ing a little, shrivelled grain ? How may the quality of seed be im- 
proved ? In wheat ? Of corn ? Why do ears from stalks bearing 
double produce the same kind ? Advantages of importing seed ? 

436, 437. Circumstances to be noted in determining the variety of 
seed ? Productiveness ? Why ? Market value ? Nutritive value ? 
Why should oat-seed be frequently changed ? 

438,439. First step in jcirejt)a7-(7?eo« of seed? Cleansing seed-wheat? 
Spring-wheat? Influence of clean seed upon the quality of flour? 
Means of procuring clean seed-wheat ? 

440-443. Advantage of steeping seed-grain ? Influence on insects, 
&c. ? Salts used in the solution ? Which are most powerful in their 
influence ? (a) First recipe ? (6) Second ? (c) Third ? Other solu- 
tions ? 

444-447. What of time of planting? Of crops planted in Autumn? 
In Spring ? Time for planting corn ? Advantages of early planting ? 
Seasons for potatoes ? First ? Second 1 



208 INDIAN CORN. 



CHAPTER XVII. 

INDIAN CORN {MAIZE). 
t 

448. Preparation of Soil. — Principles have already- 
been given, which were designed to be of general application 
in reducing soils to their proper mechanical and cheuiical 
condition. A few special directions on this subject may be 
useful, as applicable to the culture of particular crops. 

449. The most important point in the preparation of land 
for corn is deep, tliorourjh ploicinrj. For this, more than for 
any of our grain crops, the sub-soil plow is demanded — pre- 
ceded by draining, where this is necessary. Corn roots run 
deep enough to avail themselves of the benefit of all the soil 
which the plow can break. The earing-season of corn, too, 
is a period of frequent droughts; but we have shown, in 
Chap. XIII., that draining and sub-soiling are the best safe- 
guards against such contingencies. 

450. The time of plowing should be determined by the 
quality and condition of the soil. The winter frosts are of 
great service to stiff clay and slaty soils ; hence, the advan- 
tage of plowing them in Autumn or early Winter. When 
the field is covered with a clover sod, or grass which is easily 
killed, or with litter easily rotted, it is considered a good 
plan to break up with the surface-plow alone, in the Fall or 
Winter, so as to cover the sod or litter, and let it lie in that, 
condition until near planting-time. It will then be suffi- 
ciently rotted to become readily mingled with the soil. The 
same plow should be again used, and be followed by sub- 
soiling. The decayed sod and litter will, during this second 
plowing, be partly turned up to the surface, and partly 



INDIAN CORN. 2G9 

mingled with the surface-soil, giving it both a warm and 
meliGW character ; while the sub-soil plow will open the way 
for the roots to run far down, in their search for food and 
drink. 

451. There are some grasses which are not easily killed 
with the plow, and which form a very tenacious sod. The 
varieties of blue grass, common on limestone lands, are of 
this character. A favorite method of treating such a sod, 
when broken up for corn, is to turn it down during the 
Winter, or very early in the Spring, and, at planting-time, 
run the harrow or cultivator over the top, so as not to dis- 
turb the sod, but leave it with its grassy surface still more 
completely concealed, and pressed down upon the bottom of 
the furrow. The rows for planting are then opened by a 
small bar-share plow, run so shallow as not to turn up the 
sod, but only to cut through the upturned part of it. The 
corn is thus planted in the inverted sod. The early culture 
is shallow, still not breaking the sod to any considerable 
extent. Such preparation, when accompanied by sub-soiling, 
is almost certain to produce a good crop. The advantage of 
leaving the sod so long undisturbed, is, that it may have 
time for complete decay, and thus become food for the crop 
at the period of its most rapid growth. Alluvial, and all 
loose soils containing much organic matter, need not be 
broken until near the time for planting. Weeds and grass will 
not then have an opportunity of commencing their growth 
much in advance of the corn. Soils cannot often be made 
too mellow for corn, nor be kept too mellow during its growth. 

452. The distance apart at which corn should be planted, 
should vary with the richness and physical properties of the 
soil. A very fertile soil can of course sustain a greater 
number of stalks than one which does not equal it in strength. 
But of two soils, both equally fertile, the one of stiff clay and 
the other of dark loam, the latter will bear closer planting than 

23* 



270 INDIAN CORN. 

the former, because it absorbs more freely the light and heat 
of the sun. 

Yet in every case, there is a limit to the number of stalks 
to be left upon the ground ; and young farmers are more apt 
to err in having their corn too thick, than in having it too 
thin. The crop demands more than simply an abundance 
of nutrition from the soil ; it demands a full supply of both 
liijlit and heat, with free circulation of air. Corn, more than 
any other grain crop, is injured by being so much crowded 
as to exclude the free access of light and heat from the sun, 
or prevent ready circulation of air. 

453. Modes of Planting. — There are two modes of 
planting practised by the best farmers, both of which have 
their advantages under peculiar circumstances. By one of 
these modes, the ground to be planted is marked off with 
furrows all running in the same direction, and parallel to one 
another, and at the proper distance apart for the rows. If 
the land is level, or nearly so, the rows are generally made 
straight; but if the land is hilly, they are made to wind 
around the faces of the hills, in such a way as to be nearly 
horizontal. The v,'idth of the spaces between the rows varies 
from three and a half to five feet. The corn is then dropped 
into the furrows, at from one to three feet apart, and covered 
with the hoe or plow to a depth which should not exceed two 
inches, unless the soil is very dry. "When the hills are so 
near as one foot, only one stalk should be left in each hill ; 
and even then there will be too many stalks in the rows for 
any but the best lands. If the hills are two and a half or 
three feet apart in the rows, two stalks may be allowed to 
grow together. The only advantages arising from having 
the hills wide enough apart for two stalks, are the greater 
convenience in hoeing, and the more free access of light and 
heat to the soil. But, for the absorption of food from the 



INDIAN CORN 271 

soil, thei'e is some advantage in having the plants equally 
distributed in the row, each standing alone. 

454. The other mode of planting differs from this, in the 
method of arranging the rows. The land is laid oif in two 
directions, at right angles to each other, so that one set of 
furrows run lengthwise, and another set run across the field, 
dividing the whole into little squares. At the corners of 
these, where the furrows cross each other, the corn is planted. 
The rows must be wide enough for the plow to be conve- 
niently run both along and across the field. In the large 
varieties of corn, which are almost exclusively cultivated in 
the Southern States, two stalks are as many as will grow to 
full vigor in one hill. 

455. The principal advantages of this method are : (1) 
That the quantity to be cultivated on the field may be per- 
fectly regulated by the width of the rows. Each square, 
formed by the intersections of the rows, will correspond with 
the space occupied by each hill of corn ; or, in other words, 
there will be just as many corn-hills in the field as there are 
squares marked off by the rows, provided we reckon the 
margins along the fences as divided into half-squares. If, 
then, the rows are three feet apart each way, there will be 
two stalks (or one corn-hill) for every square yard of surface. 
If the land is tilled to the depth of a foot, each corn-hill will 
have the third of a cubic yard (equal to nine cubic feet) of 
soil to sustain it. When the soil is light, the number of 
stalks may be regulated to suit it, either by thinning to one 
stalk in each hill, or by increasing the distance between the 
rows, and leaving two stalks in the hills. (2) The plowing 
may be made more complete in the future culture of the 
crop, when there are two systems of rows crossing at right 
angles. Two successive plowings may be made to cross in 
the same way, and thus the soil is broken on all sides of 
the hills. The stirring of the soil is thus very complete and 



272 INDIAN CORN. 

the grass and weeds are more thoroughly eradicated than 
they can be by the plow running only in one direction. (3) 
The sun has free admission to the soil. This method cannot 
be conveniently practised on steep land. 

456. Quantity or Seed. — Each hill should have two or 
three times as many grains as there are stalks to be left grow- 
ing. By this means, if the seed has been carefully selected 
and kept in a dry place, and the ground is in a good condi- 
tion, the trouble of re-planting may be avoided. Another 
great advantage arising from an abundant application of seed 
is, that however perfect the grains may seem to be when 
planted, some will produce vigorous and healthful plants, 
while a few, at least, will produce only such as are feeble 
and sickly, and can never by any subsequent culture be made 
vigorous and productive. Five or six grains in a hill will 
almost always secure enough of the best quality to be left, 
while those of less promise may be pulled out. The trouble 
of thinning out in this case, will be amply rewarded in the 
future crop. 

Corn is often planted by machines constructed for the pur- 
pose. These should be so made that the distance between 
the hills, and the quantity of seed dropped, can be regulated 
to suit the soil. 

457. Experiments. — Every farmer should test the capacity 
of the different parts of his land for corn, by actual experi- 
ment. He should, on different parts of the same quality of 
soil, try the cultivation of one, of one and a half, of hoo, and 
of ftt-o and a ZiaT/" stalks for every square yard of surface, until 
he finds out the number best suited to that soil. He will 
then know how thick to plant his corn on different parts of 
his farm, and will establish rules for himself far superior to 
any he can find in books. 

458. After-culture. — The points of first importance in 
the culture of corn, after the planting has been properly exe- 



INDIAN CORN. 2,6 

cutcd, wee, first, to keep the ground clear of everything •wliich- 
has the same period of growth, except the crop; and second/^, 
to stir the soil thoroughly, and to as great a depth as possi- 
ble, during the early stages of the corn's growth. In clay 
soils on which a strong grass sod has not been turned down 
(§ 450), a good plan is to run a coulter, made like that of 
the sub-soil plow (§ 339), about twice on each side of the 
row, soon after the corn comes up. The middle spaces may 
be stirred with the shovel-plow or cultivator. The process 
of hoeing and thinning may then follow. After this, another 
deep plowing will generally be sufficient. 

Many fiirmers, especially in the South, prefer the plan of 
running a small mould-board plow as near the rows as possi- 
ble, at the first Avorking, in such a way as to throw the earth 
off from the corn; following with the hoes, to cover again 
any roots that may be too much exposed. This is followed 
by a second use of the same plow, run in an opposite dii'ec- 
tion, so as to throw the earth back again towards the row. 
This method has some advantages, and is adopted in the cul- 
tivation of some other crops. In the first place, it gives free 
access of air to the soil about the roots of the crop, and gives 
the portion turned twice with the plow a complete stirring. 
Secondly, it destroys completely the first weeds and grass 
which spring up near the rows. 

As corn approaches the period of tasselling, the roots 
spread with great rapidity, after which deep tillage will, by 
breaking the roots, generally result in a degree of injury 
greater than any benefit arising from stirring the soil. All 
work, after the corn has grown to the height of four or five 
feet, should be done with the cultivator and hoe. The land 
may thus be kept clean, while the roots are left free to run 
out on all sides in quest of food, until they form a net-work 
entirely across the spaces between the rows. 

459. Harvesting. — The harvesting of Indian corn has 



271 INDIAN CORN. 

reference to two points; (1) the preservation of the fodder, 
and (2) the preservation of the grain. For securing the 
fodder, there are two methods adopted extensively in almost 
all parts of our country, both of which are so familiar to 
every one living in a corn-growing region, that a very brief 
notice of each, with its advantages and disadvantages, will 
be all that is necessary. 

{a) Blading and tojiping are performed where the securing 
of the fodder within the smallest compass, and in the most 
portable form, is desired. The blades below the ear, with 
the first one above, are stripped from the stalks with the 
hands, and placed in handfuls between stalks standing close 
together, until they are sufiiciently cured to be tied up in 
small bundles, and secured in stacks or under shelter. The 
blades are in order for being tied, or in any way handled, 
only in the mornings and evenings, and on cloudy days. If 
they are handled in dry weather, especially if it is windy, 
there is always considerable loss from their breaking into 
fragments. 

Topping consists in cutting off the portion of the stalk 
above the ear. The tops thus cut are allowed to lie in small 
heaps, until they are partially cured. They are then tied 
into bundles, and several of these put together so as to form 
shocks. In this condition they stand till they are perfectly 
cured ; that is, until the stalk, as well as the blade part, has 
become dry enough to prevent moulding when placed in 
larger bulk. The next step is to secure them against the 
weather by stacking, or putting them under a shelter. 

In parts of the country remote from high markets, and 
where provender is abundant, the blades are usually regarded 
as not worth gathering. The tops, being much more valu- 
able, are frequently cut, while the blades are left ungathered. 

Both blades and tops, when secured without much expo- 
sure to rain, are about equal in value to the same weight of 



INDIAN CORN. 275 

good hay. But to secure the full forage value of tops, they 
must be cut into small fragments, so that the animals to 
which they are fed may be able to masticate them easily. I 
have found, when com tops are finely cut, and mixed with a 
little meal, and water enough to make the meal adhere to 
them, that my horses consume almost every fragment, and 
thrive remarkably well. 

After topping, the corn is left upon the stalks until it is 
sufficiently dry for the crib. It is then either pulled off with 
the shuck (husk)* still on it, and taken to the barn to be 
stripped and thrown into a well-ventilated crib, else shucked 
upon the stalks, the shucks and stalks being left together 
upon the ground. 

(6) The second method is to cut the stalks off at the sur- 
face of the ground, as soon as the ears have become hard, 
and set them up in small stacks (or shocks), to be cured by 
the air which circulates freely through them. In this con- 
dition the ci-op stands till the grain is dry enough to be put 
into cribs. It is then shucked, generally without being 
pulled off the stalk. The fodder, including the shucks, is 
then most commonly fed to cattle without cutting. The 
blades, shucks, and a little of the slender part of the stalk 
are eaten, while the remainder is trodden down, and forms 
valuable litter. 

(c) A third method is that of allowing the whole plant to 
stand untouched until the corn is ready to be gathered. Then 
after the crop has been removed, cattle are allowed to gather 
what they will of the standing fodder. In this case, the 
fodder is of little value. 

(cZ) In the Western States, where much larger crops are 
cultivated than could be secured by either of the methods 
above given — where the market is distant, or the great abun- 
dance of corn makes the price low, and where the object is 
to concentrate the crop into the more portable form of beef 
* "Shuck" is the word in common use in the South and South-west. 



27() INDIAN CORN. 

and pork, the beef cattle are turned into the field of standing 
corn to eat as much as they choose, and tread down at plea- 
sure. Hogs are next made to follow and gather up the re- 
mainder. Sometimes hogs alone are allowed to gather the 
crop. Of course this wasteful method can only be practised 
whore the price of corn is low iu comparison with the price 
of labor. 

460. Advantages and Disadvantages. — These several me- 
thods of harvesting corn have their advantages and disad- 
vantages; and the one to be pursued must be determined 
upon by each farmer for himself, according to the circum- 
stances by which he is surrounded. The method (a) has 
the advantage of securing the fodder in the most portable 
and most valuable form; and if the locality is one in which 
such provender commands a high price, this is no inconside- 
rable part of the crop. It is especially desirable in places 
where hay is not easily made. But it has the disadvantage 
of making a lighter crop of grain than either of the other 
plans given. The reason of this is, that the growth of the 
corn ceases almost entirely as soon as the blades and tops are 
removed. Although the grains may have become firm 
enough for the crop to be fully dried at gathering time, they 
shrink more, and will be found to be more loose upon the 
cob, than in the case in which the whole plant has been left 
standing for the same length of time, showing that it is not 
the more complete drying in the one case which makes the 
grains appear lighter than in the other; for in these two 
cases the opportunities for shrinkage, under the influence of 
drying, are the same. 

461. The rule given in §468 for cutting wheat, is not so 
fully applicable to corn. Wheat has its highest value before 
the stalk is fully ripe ; but corn has not reached its highest 
value until the grains have become fully hardened, and 
glazed upon the surface. This is not generally completed 



INDIAN CORN. 277 

until the blades below the ear are nearly all dead, the shuck 
partially brown, and the upper blades beginning to die ra- 
pidly. In that state the corn may be topped without injury, 
or may be cut off and removed from the ground. But the 
value of the fodder is then greatly diminished. The bran 
of corn does not, like that of wheat, increase much in 
thickness from being allowed to stand until it is " dead 
ripe." 

The method (i) has the advantage of securing the whole 
stalk for both fodder and litter, while the corn is well se- 
cured, provided the stacks are made small, so that the air 
can circulate- freely, and prevent moulding. If the corn is 
to be immediately succeeded by a wheat crop, this method 
has the additional advantage of clearing the land for the 
plow. In fact, it is the only method by which the ground 
can be brought into a good condition to be seeded down with 
wheat. The chief disadvantage attending this plan, is the 
heavy labor of cutting and stacking the corn, and the incon- 
venience of managing the bulky mass of fodder which it 
gives. 

The advantages of (c) are, first, the saving of labor, in 
case it can be more profitably expended on something else 
than the gathering of fodder; and, secondly, the securing 
the heaviest product of grain which the soil, culture, etc. 
could produce. The disadvantages are, first, the almost en- 
tire loss of the fodder; and, secondly, the greatly inferior 
value of the stalks for improving the soil, below what would 
result from using them for litter in the barn-yard. The lat- 
ter objection to both a and c plans, may be removed by 
gathering the stalks after the corn has been removed, and 
using them as litter. 

Labor-saving is the only advantage the last (r7) method 
can claim. It saves the labor of gathering the crop, and 
leaves the manure produced in feeding spread upon the land, 



278 QUESTIONS. 

■without the labor of hauling. Its disadvantages are too ob- 
vious to require even to be mentioned. 

462. Cribbing. — The crop should be allowed to become 
as thoroughly dry in the field, as the season and the time 
required for gathering will justify. Every experienced far- 
mer knows how readily corn becomes musty, when thrown 
into a large bulk in a damp condition. This often takes 
place around the cob, when the external condition of the ear 
indicated entire dryness. The cob parts with its moisture 
very slowly, and generally contains a great deal when the 
corn is cribbed. To guard against damage from this source, 
cribs should be well ventilated. The walls should have 
numerous openings for the free admission of air. The floor 
should be elevated at least a few inches (or, still better, a 
foot or two) above the ground. If the floor is made close, 
strips should be put across it which will hold uj) the corn 
sufticiently to allow a free circulation of air. If the body 
of the crib is large, poles or laths extending across from 
side to side, at various points, especially for the first few feet 
above the floor, will aid in the circulation of air, and conse- 
quent drying of the corn. 



QUESTIONS ON CHAPTER XVII. 

448 — 452. Wh.at is the most important point in preparation of soil 
for corn? Why is sub-soiling important? How is the time of plow- 
ing determined? Treatment of clover-sod? Its second plowing? 
Treatment of stiff grass-sod? Planting on such sod? Preparation 
of alluvial and sandy soils ? How is the distance between corn-rows 
and hills determined ? Danger of planting corn too thick ? 

453 — 457. First mode of planting mentioned ? Describe it. Width 
of spaces? Distance between the hills ? Second method ? Laying 
off the ground? First advantage of this method? To determine 
the space appropriated to each hill ? Second advantage ? Third ? 
How many grains to the hill ? Why? Use of machines in planting 
corn ? How should every farmer test his soil ? 



QUESTIONS. 279 

458. First point in after-culture of corn? Second? What if the 
soil is stiff sod ? What, if not ? Plow to be used ? Hoeing and 
thinning? Method of turning the mould from the row? Advan- 
tages ? When should deep tillage of corn cease ? 

459 — 462. The two points to be noticed in harvesting Indian corn? 
(ff) How are blading and topping conducted? Value of blades and 
tops? [b) Process of cutting up corn? How is the fodder used ? 
(c) Third method? {d) Method in the Western States? Advantages 
of method (a) ? Is corn injured, like wheat, in becoming " dead- 
ripe"? Advantages of method (6)? Methods (c and d)t Condi- 
tion of corn befoi-e cribbed? Why? Construction of cribs? Ven- 
tilated how? 



280 WUEAT AND OATS. 



CHAPTER XVIII. 

WHEAT AND OATS. 

463. Preparation op Soil. — Deep plowing is not so 
important for wheat or oats, as it is for corn, because their 
roots do not naturally run so deep ', nor does their season of 
growth so frequently subject them to drought. But a point 
of great importance in the preparation of land for wheat 
especially, is that it shall be as dean as possible at the time 
of sowing. Grass and other green substances, whether they 
are plowed down just before sowing, or left strewed over the 
surftice after the sowing is completed, are often injurious, 
and seldom beneficial, to the crop of wheat. So when straw, 
or litter of any kind, is spread over wheat in Autumn or 
early Winter, more harm than good generally results from 
the application. The injury is supposed, by some judicious 
formers, to be owing in part to the fact that the litter serves 
as a harbor for chinch-bugs and other mischievous insects, 
and in part to the fact that the shading caused to the green 
crop makes it too tender near the root to stand the severities 
of winter so well as it would without such covering. (^Jour- 
nal State Agricultural Society, vol. ii. p. 69.) 

464. When green crops or unrotted manures are plowed 
down for wheat, it should be done in the summer, that they 
may be well decayed, and ready to feed the newly-planted 
crop In the first stages of its growth. Clover, peas, and other 
leguminous plants having considerable quantities of nitro- 
genized matter in them (§370), undergo speedy decay; and 
may, therefore, be plowed down at a later period than would 



WHEAT AND OATS. 281 

be suitable for most other crops. The time for this kind of 
fallowing of grass and clover-fields, must of course vary, to 
some extent, with variations in climate, soil, and exposure. 

465. The cultivation of such crops as tobacco and potatoes, 
is found to be one of the best means of preparing a soil for 
wheat. The benefit in these cases seems to arise chiefly from 
the clean condition in which they leave the soil. There is 
also a probability, at least, that these, as well as some other 
crops, leave the soil in a favorable chemical condition for 
wheat. The rotation of wheat after corn is regarded, by our 
best Valley farmers, as affording but a doubtful chance for a 
good crop. The chances after oats are regarded as much 
more favorable, especially if the oat stubble is turned down 
early, that it may rot, while the scattered grains left upon 
the ground may spring up, and be destroyed during the 
seeding of the wheat. 

466. Manuring. — Some farmers put off the application 
of their stable and yard manures to wheat, until winter or 
spring. When this is done, they are usually but poorly 
compensated for their labor. Winter wheat has two periods 
of growth : the first in Autumn, and the second during the 
following Spring and Summer. The vigor of the crop, in 
its second period, generally depends very much upon the 
healthful development of those parts of the roots, which are 
natural to the first, or Autumn period. If, then, manure is 
incorporated with the soil at the time of sowing, the impulse 
given to the wheat plants in Autumn is almost certain to 
continue until the crop is matured — unless some phi/sical 
cause come in to prevent it, such as drought, or the depre- 
dations of insects. But when manure is spread upon feeble 
wheat in Winter or Spring, it comes too late. The basis of 
a good crop is not there. As well might you expect to make 
a great ox from a stinted calf, as to make a good crop in such 
a case as this. 

24* 



282 



WHEAT. 



467. Modes of planting Wheat. — There are two plans 
pursued very largely in the planting of wheat. (1) The old 
method of sowing broadcast with the hand is still kept up 
on nearly all of the small ferms, as well as many of the larger 
ones, throughout the Union, but especially in the South. 
The slovenly method of sowing the grain among the standing 
corn crop, and covering it with shovel-plows or cultivators, 
is fast passing out of flivor. The custom of breaking up the 
ground, whether fallow or corn and oat stubble, &c., with 
the large plow, then sowing and covering with the harrow, 
cultivator, or shovel-plow, is still extensively prevalent, and 
is well suited to many soils, particularly the tenacious clays, 
which retain the roots of wheat firmly, during the frosts of 
winter. (2) Drilling has, within a few years past, been 
rapidly gaining favor among our progressive agriculturalists. 
The majority of those who have tried this method would be 
entirely unwilling to give it up. The annexed figure (48,) 

Fig. 48. 




will assist those who have not seen the " drill," to form a 
tolerably correct idea of its mode of operation. The drawing 



WHEAT. 283 

is taken from the " Southern Planter," and represents 
Bickford and HuiFman's Iron-cylinder Drill. This Instru- 
ment has "attachments" for sowing guano and grass seed. 
A glance at the machine will enable any one to see that the 
lower part of each of the tubes, which extend downward 
from the axle to the ground, will open a small furrow as it 
moves forward. Through an opening near the bottom of 
the tube, and immediately behind it, the grain is discharged 
so as to fall into the open furrow. Then, as the machine 
moves forward, the soil falls into the furrow behind the tube, 
and covers the grain which has been deposited there. A 
contrivance within regulates the quantity discharged. With- 
out attempting any further description of this apparatus, let 
us see what are some of the most important results of its 
operation. 

(o) The quantity of seed may be regulated to suit the 
quality of the soil, the climate, and the time of sowing. 
Some soils bear heavier seeding than others. In climates 
where the winters are severe, some of the plants almost always 
perish, and for this some allowance must be made in deter- 
mining the quantity of seed applied. So northern exposures 
require more seed than those inclining to the south and east. 
Late sowing, if it be near the beginning of Winter, requires 
an increase of seed, because the roots, not having time to 
gain much vigor before Winter, will send up fewer stalks in 
the Spring than they would have done, if more time had 
been allowed for their first stage of growth ; hence, a greater 
number of roots will be required to yield a full crop. 

(6) A smaller quantity of seed is required than is used on 
the same soil in broadcast sowing, partly from the uniformity 
with which they are distributed, and partly from the increased 
.vigor given to the plants by the admission of light and air 
between the rows. These circumstances cause the roots 
to send up a large number of stalks. The drill is supposed 



281 WHEAT. 

to save about one-third of the seed. On a farm of even 
moderate size, this saving would very soon amount to the cost 
of the machine. 

(c) The depth is uniform, and may be suited to the soil. 
Heavy soils require more shallow planting than light, porous 
soils. The covering, too, is complete, the grains never being 
left exposed on the surface, as is often the case where the 
plow or harrow has been used. The crop stands the winter 
frosts better, from having the roots of the diiFerent plants 
interwoven, and so matted together, as to prevent one from 
being thrown out by the freezing of the soil, without the 
mass being elevated together. This advantage is seen espe- 
cially in light and porous soils, from which wheat is so often 
entirely frozen out. 

(f?) The plants shade the soil less completely in drills 
than they do when more uniformly dispersed over the ground. 
The effect in this case is similar to that mentioned in con- 
nection with the planting of corn. Two stalks of corn grow- 
ing in the same hill, throw a shadow upon the ground very 
little larger than that of a single stalk standing alone. So, 
if the stalks of wheat are confined to narrow spaces, and even 
crowded in those spaces, the soil in which they grow gets 
the benefit of more light and heat, and of a more free circu- 
lation of air, than it could if the same number of stalks were 
more uniformly spread over the surface. The result is a 
more vigorous growth, and consequently a better crop. 

(e) Small quantities of such fertilizers as guano, plaster, 
ashes, &c., can be applied more directly to the wheat, and 
with more uniformity by the proper kind of "attachment" 
to the drill, than in any other way. The economy of fer- 
tilizers is hence very great, when they are applied in this 
way. 

Every one who farms on a sufficiently-lai'ge scale should 
have this valuable implement, and, moi-e especially, if his 



WHEAT. 285" 

soil is not such as to hold wheat strongly in winter. The 
cost (from $80 to $100,) may possibly deter one who farms 
on a very limited scale, but this obstacle may be very readily 
overcome by two or three, who have small farms near to- 
gether, uniting in the purchase of a drill which will, if care- 
fully used, serve all of them for many years. 

468. Harvesting. — The time of wheat-harvest must be 
determined by the condition of the grain. The cutting 
should be done before the crop appears fully ripe. As soon 
as the grains have passed out of the ''milk state" — that is, 
as soon as the inner part has become firm, but is still soft 
enough to yield readily to the thumb-nail when pressed into 
it — the crop has its greatest value. The straw is then of a 
greenish-yellow, and there is still a green tinge about the 
head. If the wheat is allowed to stand two or three days 
after it reaches this stage, the straw and head assume a brown 
appearance — the crop has become dead ripe. The grain 
and straw have then both become less valuable. A portion 
of the starch of the grain has been converted into bran ; and, 
according to the testimony of the best millers, it will not 
make so much nor so good flour, as that which has been cut 
when less perfectly ripe. When cut in that condition which 
gives the best grain, the straw has more starch, and more 
albuminous matter in it, and is therefore more nutritious, 
than it would be if allowed to become dead ripe. 

Long exposure to rains has an injurious effect on both 
grain and straw. The dark color thus produced is owing 
to partial decay on the surface. When this takes place on 
the surface of the grain, the decayed particles become min- 
gled with the flour in grinding, and give it a dark shade. 
At the same time, repeated wetting and drying destroys the 
nutritive substances in the straw. Wheat should, therefore, 
be placed under shelter or carefully stacked, as soon as it has 
become suflliciently dry to prevent moulding, or heating in 
bulk. 



286 OATS — QUESTIONS. 

OATS. 

469. Soil. — The best chance for a good oat crop is to sow 
it upon corn or wheat stubble of the previous year. A 
freshly-turned sod seldom yields a full crop of this grain; 
but any land of tolerable fertility, which has been under cul- 

, tivatioa the previous year, will produce a fair crop of oats. 

470. Planting. — The land should be plowed up in the 
Spring, or latter part of the Winter, and the sowing be done 
as early in the Spring as the weather will permit. It is a 
grain sufficiently hardy to endure quite severe frosts after it 
has come up in the Spring. Some varieties may be sown in 
the Fall, and will not only live through the Winter, but come 
forward more rapidly in the Spring, and ripen earlier than 
the ordinary oats. These are called " Winter oats." Their 
early progress often enables them to escape droughts, by 
which the spring varieties are cut short. This gives them 
an advantage in localities where early droughts are common. 



QUESTIONS ON CHAPTER XVIII. 

32 4()3 — 4GG. Is deep plowing important in preparation of soil for 
v?heat and oats? Why not? What point is of great importance? 
Effect of straw or litter spread over wheat in Winter? The cause? 
When should green crops be plowed down? What crops prepare 
land well for wheat ? AVhy ? What of rotation of wheat after corn ?. 
What of manuring wheat in Winter? When should manure be ap- 
plied to wheat? Why? 

4G7. First mode of planting? How conducted? Second mode? 
Describe the drill. Advantages from its use ? (a) Quantity of seed 
regulated? (6) Economy in seed? (c) Depth? Protection against 
frost? (rf) Admission of light? (e) Economy in fertilizers? 

468. Time of harvesting? When is the grain fit for cutting? In- 
jury from standing too long? Explain this. Effect of long expo- 
sure to rain? 

469, 470. Best preparation of soil for Oals? Season for sowing? 
Winter oats ? 



POTATOES. 287 



CHAPTEK XIX. 

POTATOES. 

471. Soil. — The potato will grow upon almost any soil, 
with good management and a favorable season ; but a loose, 
moist, and cool soil is most suitable. Well-drained swamps 
sometimes produce the potato with great luxuriance of 
growth. North-lying slopes of loose rich mould, gravelly 
and sandy loams, etc., are all favorable to the production of 
this important crop. 

472. Preparation.— The ground should be prepared by a 
thorough plowing in the Autumn or Winter. But if the 
land has a clay sub-soil, this should not be turned up to the 
surface; it should, however, be well broken with the sub-soil 
plow. In the Spring, at the time selected for planting, ma- 
nure should be applied either immediately before planting, 
or in the drills with the potatoes. If manure is abundant, 
the best method of applying it is to spread it broadcast over 
the soil, and stir it completely into the loose mould, to the 
depth of four or five inches, by plowing and cross-plowing as 
many times as may be necessary. If manure is not abun- 
dant, it is more economical to use it in the drills for covering 
the tubers at the time of planting. 

473. Manures. — The best manure for potatoes is fresh 
stable, or hog-pen scrapings, mixed with a large portion of 
broken straw, leaves, or other litter.* From ten to twenty 
tons per acre, as the soil is more or less fertile, should be 

* The horses and hogs can be made to do the mixing. 



288 POTATOES. 

applied, in case it is spread upon the surface. A smaller 
quantity will be sufficient when applied in the drills. When 
only a light application of this kind of manure can be afford- 
ed, a little guano may be mixed with it, very much to the 
advantage of the crop, especially on light, thin soils. 

474. Planting. — In our southern climates, the great 
enemy of the potato crop is the hot sun, and particularly 
when accompanied by drought. Our planting should, there- 
fore, have special reference to protection against excessive 
heat. The best means of accomplishing this is by mMlching. 
If the manure has been previously stirred into the soil, the 
crop should then be planted in drills, at distances varying 
from one to two feet from each other, according to the soil 
and variety of potato. The stronger soils will bear closer 
planting than those of less fertility; and those varieties of 
the potato which produce their tubers within a small space 
around the base of the stems, as we see in the Mercer va- 
riety, may be planted much more thickly than such as the 
Long Red, which sends its tubers off to a considerable dis- 
tance. 

475. After the soil has been thoroughly prepared, I have 
found, in my own experiments, that the most convenient 
method of planting is to open a furrow along one side of the 
ground (along the lower side, if not level) with a shovel-plow 
or small bar-share, and drop the tubers in this furrow, at 
distances varying from eight to twelve inches. Then, with 
the same plow, another furrow is run close to the row thus 
prepared, and the soil thrown upon the potatoes, so as to 
cover them about two inches deep. If the soil and variety 
of potato will allow of very close planting, another row of 
tubers may be dropped in this second furrow, and the soil 
from a third be thrown over upon it; the third may then be 
supplied with potatoes, and be covered with the soil from a 
fourth, and so the operation be continued till all the ground 



POTATOES. 289 

is planted. If the soil is not very fertile, or the potatoes of 
the spreading varieties, the planting should be done only in 
every second or third furrow, as the judgment of the planter 
may dictate. When this process of planting has been com- 
pleted, a large harrow may be passed over the ground, so as 
to leave it with a smooth and even surface. It will be well 
to sow a mixture of ashes, plaster, and salt over the ground, 
either before or after harrowing. The mixture should con- 
sist of four bushels of leached or two of unleached ashes, 
with one bushel of plaster, and one gallon of salt; and should 
be applied at the rate of ten or fifteen bushels per acre. 
Then the whole surface is to be covered to the depth of six 
or eight inches with broken straw, forest leaves, or some 
other form of litter. This covering (mulching) protects the 
crop against the severe heat of the sun, prevents rapid eva- 
poration, and thus secures both a cool and moist soil. Be- 
sides this, it prevents the growth of weeds, while the potato- 
shoots readily find their way to the surface. The shading 
of the ground hastens the decay of the manure which has 
been applied, thus increasing its efficiency, and also promotes 
other beneficial changes in the soil. Potatoes planted in this 
■way require no subsequent culture. If a few weeds find 
their way through the mulching litter, they can be readily 
pulled up by hand. At digging-time the tubers will be found 
very near the surface, and many of them even- lying upon 
the surface of the soil. 

When potatoes are cultivated in the ordinary way, in drills 
three or four feet apart, such manure as that recommended 
above should be spread upon the tubers in the drills, so 
as nearly to fill the furrow, then a light covering of soil be 
added. 

476. Culture. — If the methods of planting are adopted 
which require future culture, all plowing and hoeing should 
be done during the early stage of growth. No working, 
25 



290 POTATOES. 

whicli will disturb the roots, should be done after the flower- 
buds begin to make their appearance; because the period 
has then come for the rapid growth of the tubers, and they 
should not be disturbed. If weeds still prove troublesome, 
they may be removed by very shallow hoeing, and by hand. 
Deep covering at the time of planting, or heavy earthing in 
future culture, are injurious to the crop, especially in heavy 
clay soils, or in very damp localities. 

477. The flower-buds of the potato should be plucked off 
as soon as they make their appearance. The nutrition, ex- 
pended in the production of seeds, is almost identical in kind 
with that which promotes the growth of tubers. Hence, if 
eeeds are produced, it must be at the expense of food which 
would otherwise nourish the tubers. The plucking of the 
flower-buds prevents this abstracting of starch, gluten, &c., 
from the crop. Topping the vines, when they are too rank, 
has sometimes a like efi'cct. 

478. Digging. — As soon as the tops of the potatoes die, 
it indicates full maturity of the tubers, and the crop should 
then be gathered. For if the weather sliould become warm 
and moist, there is danger of a second growth, which makes 
the potato watery, from the conversion of a portion of its 
starch into dextrine. The same injury results, as is well 
known to arise from the "sprouting" of potatoes in the 
Spring. After being dug, they should be dried in the open 
air, and laid away in a cool, dry cellar. If they are to be 
buried in the earth, a dry and elevated spot should be 
selected for this purpose, and so prepared that the water 
cannot collect and stand in the bottom of the bed. They 
should not be buried until near the beginning of Winter, as 
there is then but little danger of heating, and consequent 
rotting under the influence of warm weather. Before the 
weather becomes warm enough in the Spring for the sprout- 
ing of the tubers to commence, they should be taken up, 



POTATOES. 291 

and returned to the cool, dry cellar. If tliey are damp when 
taken from the ground, they should be spread out where 
they will be exposed to the sun for a few hours. They may 
be kept in good condition for eating much longer, by being 
spread on a dry floor in a cool situation, than in any other 
way — the great object being to prevent germination. 

479. Selections for planting. — Those designed for 
seed may be conveniently selected, either at the time the 
crop is laid up in the Fall, or when spread out in the Spring. 
For planting, those tubers of medium size are best, because 
their buds (eyes) are generally more vigorous than those of 
the very large or very small ones. The object in planting 
this, as well as all other crops, should be to secure plants 
which are healthy and vigorous at the very beginning of 
their growth. 

It is well known that the part of the potato tuber, most 
remote from the point where it is attached to the root, has a 
greater number of eyes than any other part. These eyes 
are less vigorous than those more sparsely scattered over the 
parts nearer the root-cud, and will consequently give more 
feeble plants. A single tuber, of average size, has too many 
eyes for a single hill, and should, therefore, be cut in two. 
In doing this, attention should be given to what has just 
been said about the eyes. The tuber should be so split as 
to have some of the best buds on each piece. This is done 
by dividing lengthwise, or from the root-end through to the 
opposite part. 

480. Degenerating. — Potatoes are found to degenerata 
in the hands of a great many farmers, and hence an impres- 
sion prevails extensively that the same variety naturallt/ de- 
teriorates, when cultivated in the same soil and climate for 
several successive yeai's. This is true to some extent, if it 
is planted too frequently on the same land, even when the 
best modes of culture are pursued. It is also true when, 



292 QUESTIONS. 

year after year, the little worthless tubers are selected for 
planting; and when careless preparation of soil, careless 
planting, and careless culture, are bestowed upon the feeble 
plants which spring from little, half-developed tubers. Corn, 
wheat, rye, and every other kind of crop, degenerates under 
similar treatment. ]jet any farmer try the rules and princi- 
ples above given carefulli/, for a few years in succession, and 
it is most probable that he will find the quality of his crop 
advancinr/ gradually, instead of retrograding. Such, at least, 
has been the writer's own experience. 



QUESTIONS ON CHAPTER XIX. 

§471-473. Best soil for Foiatoes 9 How should the soil be pre- 
pared ? Application of manure ? If manure is abundant, how ap- 
plied ? Best manure for potatoes ? Quantity? 

474, 475. Thing to be guarded against in planting in southern cli- 
mates ? Best means? Distance of rows and hills? Convenient 
methods of planting? If the soil is not fertile, how should the dis- 
tance be regulated ? Application of ashes, plaster, and salt ? Ad- 
vantages of jnulching? Ordinary mode of planting? 

476, 477. AVhen should the culture of potatoes be performed ? 
Why ? Effect of plucking off the flower-buds ? 

478, When should digging commence? What injury from second 
growth? Suitable locality for burying potatoes? Proper time for 
burying? When should they be taken up? IIow treated? AVhy? 

479, 480. When should selections be made for seed? Which tubers 
are best for seed ? Why ? In what part of the tuber are eyes most 
numerous ? Where most vigorous ? Why should tubers be cut ? 
How? AVhy do potatoes so often appear to degenerate ? How may 
this be prevented ? 



HAY CROPS. 293 



CHAPTER XX. 

HAY CROPS. 

481. Clover. — From the three divisions of its leaf, clover 
is called "Trifolium." There are several varieties cultivated 
in different countries, but the best for our climate is the 
common rod clover (^Tri/oJium pratensc^. This is a biennial 
plant. If sown early in the Spring, and not too much shaded 
by other crops, it produces a few blossoms the first season. 
When allowed to grow the next year to full maturity, with- 
out cutting, it dies ; but if it is cut or pastured, so as to pre- 
vent it from coming to full maturity, it lives through a third 
or even a fourth summer, and retains vigor enough to pro- 
duce a tolerably fair crop. But its heaviest product is always 
in the second season after sowing. 

482. Some farmers believe that red clover is, by a myste- 
rious process, converted, by close pasturage, into another 
species called "white clover," from the color of its bloom. 
There is no doubt that the red clover soon disappears from 
a closely-pastured field, and that white clover (^TriJoUum 
repens,) springs up in its place ; but this is easily explained, 
without the necessity of supposing the change, above men- 
tioned, to take place. Red clover is naturally biennial, and, 
if left to its full course of development, will die at the end 
of the second season ; and by artificial cutting or cropping 
by cattle, can seldom be made to grow well longer than to 
the end of the third or fourth season. White clover, on the 
other hand, \^ perennial. Its seeds are almost always mixed 
to some extent with those of the red variety, and when sown 
together, the latter, being of a much more rapid growth, and 

25* 



294 II AY CROPS. 

a much larger plant, takes possession of the ground, while 
the smaller white variety is too much shaded to be distin- 
guishable beside its more prosperous companion. But the 
short-lived red crop soon runs its course and dies, while the 
white, more tenacious of life, remains in possession of the 
field, with more room to display itself as the prominent owner 
of the soil. 

483. Soil. — Clover grows best on clay loams, having a 
good supply of lime, in some available form ; but almost any 
soil (not swampy) may be made to produce a good crop, by 
frequent application of ashes and gypsum. The roots of 
clover run deep (§353), and hence require a deeply-broken 
soil. The sub-soil should be well broken in the cultivation 
of some preceding crop, when it cannot be done at the time 
of sowing the crop with which the clover is mixed. If, for 
example, corn is to precede oats, and clover is to be sown 
with the oats, a good sub-soiling for the corn crop will also 
be of great service to the clover, since the strong roots of 
clover will penetrate even a stiff clay sub-soil, if it has been 
well broken within a year or two. It is then less apt to be 
frozen out in Winter, than it is when cultivated on a soil less 
deeply broken. 

484. Sowing. — The Spring is undoubtedly the best sea- 
son for securing a good stand of clover, while March and 
April are most probably the safest months for sowing it, in 
our latitude. It may be successfully sown upon wheat or 
rye, but there is more certainty of getting it to stand well 
with oats — the ground being in a better condition for the 
seed to become covered, and for the roots to get a good hold 
upon the soil. 

485. When sown on a field of wheat, if the surface is a 
loose mould, a large harrow should be passed over the soil, 
about the last of March or early in April, and about six 
quarts of seed per acre sown immediately afterwards. li' the 



HAY CROPS. 295 

surface is somewhat liard, the clover may be sown before the 
harrowing is done, as there is then no danger of coA'ering 
many of the seeds too deep ; and the slight covering given 
by the harrow on such a soil, will protect the young plant 
from injury in the rapid drying of such surfaces. To secure 
uniformity in sowing, the seed should be mixed with some- 
thing which will increase the bulk. The seed for an acre 
may be thoroughly mixed with a bushel of ashes and a half 
bushel of plaster. The quantity to be applied can then be 
easily regulated by the hand, as in sowing wheat, while the 
ashes and plaster will fertilize both wheat and clover. The 
harrowing, which is to precede or follow the sowing, will not 
injure the wheat; but is thought by many persons to be of 
service to it. The wheat-gleaner, now so extensively used, 
is a good instrument for covering clover-seed, if the surface 
is not too hard. 

486. If clover is to be sown with an oat crop in the 
Spring, the seed should be prepared as above directed, and 
then applied immediately after the last harrowing of oats. 
The harrow passing over the ground, after the clovcr-sccd 
has been applied, would cover it too deep. The first rain 
that falls will cover it sufficiently. 

487. Cutting, etc. — If the clover crop is designed for 
hay, it should be cut at the period of its growth at which it 
has the greatest nutritive value. This occurs when about 
one-third or one-half of the heads have commenced turning 
brown. After this period, the sugar and starch which abound 
in the green stalks are rapidly converted into woody fibre, 
while the proteine matter speedily disappears. The first crop 
of the season is most valuable for hay, but the second, and 
sometimes even the third, may be cut for this purpose. The 
cutting should be so managed as to form long and regular 
swaths, for the convenience of hay-making. 

488. The leaves of clover are very abundant, and consti- 



206 IIAY CROPS. 

tute a very valuable part of the hay; but when the hay is 
dry, they are very hriitle, and liable to be wasted in making 
and stacking the crop. To prevent this loss, as far as pos- 
sible, is an important point. It is best done by letting the 
swath lie until the top is tolerably well cured, and then 
turning it over Avith a fork, without any additional tossing. 
The hay may be safely packed away in mows, or stacked, 
before it is entirely cured, if a layer of dry straw a few inches 
thick is spread over the mow or stack for every foot in depth 
of hay. The straw tends to absorb the moisture of the hay, 
and also to admit the air. If there is much greenness in the 
hay when put up, a little salt spread over it will not only 
assist in preserving it, but will make it more palatable to 
stock. The straw used in packing will be greatly improved 
in flavor by contact with the clover. (See Mr. Ruffin's 
method, § 50G.) 

489. GrATHERiNG Seed. — The second crop is generally 
best for seed; because, in the first place, the heads are usually 
better filled than those of the first crop; and, in the second 
place, because it is more clear of weeds and other foreign 
plants. The first mowing clears the soil of everything, and 
the second growth of clover springs up with great rapidity, 
and is matured before almost every other plant found asso- 
ciated with it. The crop is thus cleaner, and being less 
thickly set u}X)n the ground, it has a more favorable oppor- 
tunity of bringing its seed to maturity, than the first crop 
had. 

490. If there is no grass in the field which will eradicate 
the clover, it may be made to produce crops of hay for seve- 
ral years in succession. This is done by running a sharp 
coulter, or a sub-soil plow, through the clover very early in 
the Spring, so as to loosen all the soil, and give the seed left 
upon the land the preceding Fall, an opportunity to germi- 
nate and take root. The new plants thus produced will take 



HAY CROPS. 297 

the places of the old ones as they die out. If the soil is a 
loose loam, harrowing and rolling will answer the purpose 
better than coultering. 

491. Grasses. — We have not room for specific directions 
for the cultivation of all the grasses used in hay-making. 
Some general remarks on two or three of them must serve 
our present purpose. 

Timothy {Phkum pratcnse). — This is sometimes called 
" cat's-tail," and in some of our Northern States, " Herd's 
grass." It is a perennial, and makes hay of fine quality, 
when cut at the proper season ; and where the soil suits it, 
the crop is generally abundant. 

The Soil best adapted to timothy is a rich clay loam, 
moist, but not swampy. Alluvial meadow lands, free from 
stagnant water, and drained swamps, well subdued by the 
cultivation of a few grain crops, generally produce fine yields 
of this grass. Uplands, too, and more especially northern 
slopes of good clay loam, yield fine timothy, unless visited 
by severe drought in the early part of Summer. 

Solving. — Timothy may be sown either in early Autumn 
or in the Spring. One of the surest methods of getting a 
good stand of this grass, is to sow it with rye in the latter 
part of August. It then has time to get a tolerably strong 
root before Winter sets in, and it is, moreover, sheltered by 
the rye against the severity of frosts. If sown in the Spring, 
it may be put in with wheat, or with the oat crop. About a 
half-bushel of seed should be put upon an acre, to insure a 
sufficiently thick stand. The seed may be mixed with ashes 
and plaster, as before recommended for clover, and should 
be but slightly covered. As an ordinary harrow would 
cover many of them too deep to germinate, a very light 
brush-harrowing is quite sufficient; or, the method recom- 
mended for clover will also do well for this grass. A gallon 
of clover-seed per acre, added to the timothy, will make the 



208 HAY CROPS. 

first and second crops mucli heavier than the grass alone ■will 
produce. Then the clover, being a biennial plant, and the 
timothy perennial, the former will disappear gradually from 
the spaces it has filled, while the latter will spread out, and 
soon cover the whole ground. 

492. JIarvesfing. — Timothy has its highest nutritive value 
when the first heads begin to turn brown. A large part of 
the crop is at this time in bloom. The stalks are then suc- 
culent, and contain their largest quantity of starch, sugar, 
gum, and albumen. The hay should be cured as rapidly 
as possible, and without rain. By having the weaker hands 
engaged in tedding immediately behind the mowers, and 
then in turning, as soon as the top becomes tolerably well 
cured, it may be prepared in a few hours to be put up 
in small hay-cocks, where it will soon become sufficiently 
cured for the stack or the mow. It should be sprinkled with 
salt (5 or (3 quarts to the ton) when packed away. 

The after-crop of timothy makes a pasture of very supe- 
rior quality, for cattle, sheep, or horses. This grass also adds 
to the fertility of the land, partly by the decay of its abun- 
dant crop of blades about the root, and partly by the gradual 
decay and reproduction of its bulbous roots. 

493. Orchard Grass. — This grass will grow upon almost 
any soil which is not swampy. It may be sown in the Spring 
with clover, which it eradicates after one or two seasons. It 
has a very strong root, and is not easily overcome by other 
grasses : it is, hence, very suitable for lots designed to be kept 
in grass for a long time. It starts early in Spring, and con- 
tinues green quite late in Autumn ; and is, therefore, valu- 
able for early and late pasture. As a hay crop, it holds no 
very high place generally. When harvested for hay, it 
(should be cut in full bloom ; because the hay has then its 
highest value, and the maturing of the seed, which is ex- 
hausting to the soil, is prevented. 



HAY CHOPS. 299 

The sub-soil plow, when run beneath the sod of this grass 
once in two or three years, is of service, especially if the 
process is followed up by a top-dressing of stable or yard 
manures. Ashes and 2)l((sfcr should be used freely and fre- 
quently on all grass lands. The grasses demand an abun- 
dant supply of lime and potassa (see Table III). 

494. Pasture. — For permanent pastures, limestone soils 
are most suitable ; and where they are level, and at all swampy, 
draining is wanted, to make them yield a crop which is good 
in either quantity or quality. The most durable* and nutri- 
tious grasses for pasture are what are called " Blue-grasses." 
The Kentucky Blue-grass should, most probably, stand first 
on the list, and should be introduced into every limestone 
region. The common " Spear-grass," or greensward, is an- 
other species of the same genus, and forms fine pasture. 

The proper care of pasture lands is too much overlooked 
by many of our farmers. Worthless briars and weeds are 
too often seen to occupy much of the best soil, where a little 
timely attention and labor would have secured a rich green 
sod of sweet and nutritious grass. Top-dressing with mine- 
ral and other fertilizers, will often be found as profitable on 
pastures, as upon cultivated crops. 

In those sections of country where the perennial grasses 
will not thrive, more attention should be given to the intro- 
duction of the annuals and hienm'als, to be cut for hay. The 
annual meadow-grass and biennial rye-grass, with other va- 
rieties, have been cultivated where those of more permanent 
character will not readily take root. The different varieties 
of millet, oats cut in full bloom, and corn sown broad-cast, 
or thickly drilled, all make good substitutes for hay, on lands 
where the best hay grasses and clover are not easily or abun- 
dantly produced. 

Experiments. — Every farmer should make repeated ex- 
periments on his own lands, with various kinds of grass, that 



coo QUESTIONS. 

he iiuiy dcteruiinc which are best adapted to his soil. Then 
it sliould be an established rule : (1) jVcocr to allow a field 
to he out of clorcr, or some Mnd of grass, when it is not oc- 
cupied hy other crops; (2) Never to miss an opportunitt/ of 
fallowing with clover or grass sod. It is the cheapest way 
of enriching a soil. 

QUESTIONS ON CHAPTER XX. 

481. Why is Clover called Trifolium? Best variety for our cli- 
mate ? What is a biennial plant ? Its growth the first season ? The 
second ? When does it produce its heaviest crop ? 

482, 483. What do some believe in regard to the change of red 
into white clover? How explained? Best soil for clover? How 
ma}' any soil be made to produce it ? Why is deep plowing important? 

484,485,486. Best season for sowi'/jy clover ? On what crops may 
it be sown? How treated when sown on wheat? How is the sow- 
ing rendered uniform ? If clover is sown on oats, should it be har- 
rowed ? Why not ? 

487, 488. When should clover be c«i! /or Aery.? Why? Which crop 
is most valuable ? Why do the leaves of clover require especial care? 
Does it be.ar tossing? How may straw and salt be used for hay? 

489,490. Best crop for «eerf .? Why? Why clear of weeds? How 
may clover be made to produce good crops for several years in suc- 
cession ? How to be treated if the soil is loose ? 

491, 492. What is Timothy sometimes called? Why called a pe- 
rennial ? What soj'Zi best adapted to it? Seasons for som-'w^.^ With 
what crops may it be sown ? How much seed per acre ? How pre- 
pared ? AYhat of mixing clover-seed with it? AVhen should timothy 
hi: cut? Why? How cured? For what is the after-crop valuable? 
How does it enrich the soil? 

493, 494. Soils adapted to orchard grass ? When sown ? For what 
lots is it suitable ? Its value for pasture ? As a hay crop ? When 
cut? Why? How should it be treated occasionally? Lands best 
suited for pasture? How treated if they are level and swampy? 
Best grasses for pasture? Examples? How should pasture lands 
generally be treated ? What may be substituted for perennial grasses ? 
How should every farmer test his own lauds ? What established rules 
should be observed everywhere? 



BEANS AND PEAS. 301 



CHAPTER XXI. 

BEANS AND PEAS. 

495. Value. — There is a large class of plants which have 
their seeds enclosed in a sort of bivalve pericarp, usually 
called a ''pod." These are called "leguminous" plants. 
The different kinds of hean and pea are examples of this 
class. The varieties of clover are also leguminous, having 
their seeds enclosed in pods. Red clover has usually one 
seed in every pod, but some kinds of white clover have seve- 
ral together in the same pod. 

496. This whole class of plants is remarkable for the 
quantity of nitrogen they contain. The nitrogen is chiefly 
found a.s one of the constituent elements of a proteine body, 
which we have called "legumen" (§ 157). All the proteine 
compounds have been spoken of as possessing a high nutri- 
tive value, and as forming a most important ingredient of 
animal food. They bear a relation to animal nutrition some- 
what similar to the relation of ammonia to plant nutrition. 
The legumen of beans and peas is so abundant as to place 
them above both wheat and corn in nutritive value. On this 
point more will be said hereafter. The stalks of these plants 
also abound in proteine matter, and in that respect resemble 
clover hay in composition and value, and hence make excel- 
lent rough forage for stock. 

497. We have learned that, when proteine substances un- 
dergo decay (§ 159), ammonia is always one of the products. 
This has also been mentioned as the most valuable ingredient 
in organic fertilizers. If, then, bean and pea crops are plowed 
into the soil at the proper period of growth — that is, at the 

26 



302 BEANS AND P K A S . 

period when tliey contain the greatest amount of protcine 
matter — considerable quantities of that most important fer- 
tilizer, ammonia, are generated in the soil. Clover was once 
regarded as almost the only suitable crop to be employed as 
green manure, but experience has shown that other legumi- 
nous plants have a similar value ; and, in some climates and 
soils, certain varieties of beans and peas seem to be even 
superior to clover for the purpose of fallowing. 

498. Varieties. — DiiFerent latitudes require different 
varieties. Those only which have a comparatively short 
period of growth, are adapted to the Northern States. Such 
are the China Bean, Horse Bean, and the different varieties 
of Field Pea. Those which require a longer season and 
more hot sun, are confined chiefly to the Southern States. 
There is a species of hean cultivated extensively in some of 
the older Southern States, of which there are a good many 
varieties. All the varieties are embraced under the general 
names of ''Cornfield Pea" and " Southern Pea." Mr. Ed- 
mund Ruffin, Sr., in his valuable Essay on this crop (for 
which a premium was awarded by the Virginia Agricultural 
Society, 1854), enumerates nine varieties. (1) "The buff- 
colored pea, usually called either the cow or day pea.^' (2) 
'' The Bass (red) pea, used extensively on the Lower Roan- 
oke, in N. C." (3) " The hiack-ryc pea, of several varie- 
ties, was formerly most generally known, and indeed was 
almost the only kind cultivated." (4) " The early black 
pea has perfectly black and large seeds." (5) " The mottled 
or shinney pea, which has been so much celebrated in latter 
years, differs in some respects from all others. The seed are 
of a light brownish color, thickly streaked or mottled with 
deeper brown." (6) "Large black or Tory (late) pea." (7) 
" Small black and late pea." (8) " Green-eye white pea." 
(9) " The small green or bush pea " — sometimes called 
" Chickasaw" and " Oregon Pea." But these are by no 



BEANS AND TEAS. 303 

means all the names applied to the varieties of " Southern 
Pea; for the same variety passes under different names in 
different sections of the same State. '' This kind only, of 
all enumerated and described here, seems to be a true pea ; 
and, therefore, is not of the same species with all the other 
kinds here termed varieties of the Southern Pea." 

499. Climate. — The different species of bean have the 
quality of gradually adapting themselves to different lati- 
tudes, at least to some extent. If the pods which first come 
to maturity are always selected for seed, the time of ripen- 
ing may be made to occur several weeks earlier, after a few 
years' culture. At present, the Southern Pea is not much 
cultivated north of 37° 45', nor will many varieties come to 
maturity so far north as this, in an ordinary season. But 
with proper attention several of them might, most probably, 
be adapted gradually to still higher latitudes. Their great 
value, for both forage and manure, would certainly justify a 
fair experiment on this point. 

600. Some of the earlier kinds, such as the ''Early 
Black" [(4), above] and the "Shinney" (5), are thought to 
be best adapted to the climate of Virginia ; taking into con- 
sideration the time of maturing, and their productive value 
for feeding and fallowing. For table use some of the lighter 
colors are generally preferred, such as the "Black-eye" and 
" Green-eye White Pea." In more southern latitudes, the 
" Shinney," " Clay," and "Bass," are among the varieties 
preferred, and most extensively cultivated. 

501. Soil. — Crops of this class will grow well on almost 
any kind of land not deficient in lime. The best soil for 
beans is a warm, sandy loam, of medium fertility. A very 
rich soil produces a most luxuriant growth of vines, espe- 
cially in the "Southern Pea;" but the quantity of seed is 
then but small. On medium quality of soil the crop of vines 
is not so heavy, but the grain crop very abundant, provided 



304 BEANS AND TEAS. 

the culture and season have been favorable. The very 'poor 
soil will generally produce a crop sufficient, when turned 
under, to add considerably to its fertility. This is proverb- 
ially true in the culture of the Southern Pea. Land in lower 
Virginia, which "will not produce Black-eye Peas," is re- 
garded as in rather a hopeless condition. South of 37°, 
almost an}' soil may be restored to fertility from the most 
exhausted condition, by cultivating the pea, with the appli- 
cation of some form of lime ; either marl, caustic lime, gyf- 
stim, or ashes, attended with proper rotation, and as frequent 
fallowing as possible. 

502. Plowing, for bean and pea crop, should be deep and 
thorough. The roots penetrate a well-broken soil to a great 
depth ; and as the plant gathers mineral substances largely 
through its roots, especially lime and potassa, with sulphuric 
and phosphoric acids, these will be transferred from the lower 
to the higher parts of the soil, and be left by the decaying 
crop in a good condition to form the food of succeeding crops 
of grain, tobacco, cotton, etc. 

503. Planting. — The methods adopted for planting may 
vary with the object to be attained. If the crop is cultivated 
for its grain and forage, the largest yield can be obtained by 
cultivating in rows, varying in distance according to the kind 
of bean or pea to be planted. The varieties which grow erect 
(bush-beans) may be planted in rows two or three feet apart. 
Those which spread their vines, like the Southern Pea, 
should be in rows from three to four and a half feet. The 
seed may be drilled in the rows, or planted in separate hills. 
If the object is to prepare a crop for fallow, the land should 
be well prepared, and the crop sown broadcast, and covered 
with the harrow or cultivator. 

504. The Southern Pea has been cultivated in the Southern 
Atlantic States from time immemorial. Some of the methods 



BEANS AND PEAS. 305 

pursued in Virginia, and the States farther south, arc the 
following : 

1st. " The oldest and still most extended culture [in Vir- 
ginia], is to plant the peas after and among corn. When 
the corn is mostly about 8 or 10 inches high, and has been 
just plowed and hoed, peas are planted, either in the nar- 
row intervals between the stations of corn, if in drills; or 
otherwise, in a plowed furrow, the last made by the plow in 
the middle of the wide intervals between the corn rows. In 
either case, usually 10 or 15 peas are dropped together, and 
come up and grow in a cluster. So many seeds are put to- 
gether, for the 3'oung plants to better force their passage 
through the earth. But some experienced cultivators of 
North Carolina think that 5 or 6 plants together, produce 
better than a greater number. One more plowing is all that 
is afterwards given to the corn — which, at very little more 
trouble, is all the culture required for the peas. 

" 2d. The next most extensive, though, in Virginia, a 
very recent mode of pea-culture, is also as a secondary crop 
amongst corn, but made by sowing broadcast, when giving 
the last horse-tillage, and covering the seeds more or less 
perfectly by that tillage process. This costs but the seed 
and the labor of sowing. The crop all goes for manure, and 
is seldom ripe enough (in Virginia) for good manure. 

" 3d. The third mode, and, as I think, the cheapest and 
best, to raise the pea-crop for manuring, is to sow tho seed 
broadcast, on a separate field, or without corn." — Edmund 
Hvffin's Essay, Ya. IS. Ag. Soc. 

" In sowing peas broadcast as a fallow crop, in preparation 
for wheat or other crops, the land should be broken up in 
the Winter deeply, and about the first week in June (in our 
latitude), the peas sowed at the rate of one bushel or five 
pecks to the acre, and either harrowed in with a heavy har- 
26* 



300 BEANS AND PEAS. 

row, or plowed in with single plows, according to the state 
of the land." — P. M. Eclmomhtoii, of North Carolina. 

4th. " In planting as a separate crop, break up the land, 
if possible, in Winter; and at the time of planting (which 
in this latitude is best during the first fifteen days of June), 
run oiF the land in rows 4, 42, or 5 feet distant, either by 
running one furrow, or listing with three furrows, according 
to the condition of the land. If it is grassy, it should be 
listed — drop the peas from two to three feet distant in the 
row, from ten to fifteen peas in a hill, and cover with the 
hoe, harrow, plow, or cultivator with the front hoe removed. 
After the peas have made two or three of the second leaves, 
run the bar of the plow as near as possible, throwing the 
earth from them, as in the first working of corn, and, if 
necessary, throw out the middle and run over them with the 
hoe, cutting out the grass and weeds, and a little after the 
vines have commenced to run, plow again, throwing the 
earth to them. This is all the cultivation necessary; and on 
fertile land, with favorable seasons, it will give a good return 
for the labor spent — say an average of sixteen or twenty 
bushels to the acre, which, at seventy-five cents per bushel, 
will equal twelve or fifteen bushels of wheat, at one dollar 
per bushel. This method of planting will take about one 
peck and a half, or three half-pecks, to the acre." — Llem. 

This last method is best when the peas are to be gathered, 
not only because the mode of culture brings a better crop, 
but because of the greater convenience of gathering. It has 
the further advantage of leaving the land in a condition free 
of grass and weeds, and hence in a better state of preparation 
for the succeeding crop. Some farmers prefer it even for 
fallows, because of the greater certainty of getting a good 
stand of peas when planted in this way. 

When peas are planted with corn, they do not seem to in- 
terfere, to any great extent, with the growth of the corn 



BEANS AND PEAS. 307 

crop ; because the latter is well matured before the peas 
reach their stage of most rapid growth, provided they are 
not planted before the corn approaches the time of tasselling. 

505. Gathering. — "When the pods are ripe, or enough 
of them to provide as much seed as is wanted, they are 
picked off by hand; and when sufficiently dry, are threshed 
out with flails or sticks, or are run through a threshing ma- 
chine. If the greater part of the crop is intended for ma- 
nure, it should be plowed down as soon as the gathering is 
finished. The seeds are believed to have a higher fertilizing 
value than the vines, if they come to maturity; but by this 
time the vines have lost part of their value. The question 
as to the proper time for plowing down resolves itself into 
this form: "When will the seeds and vines together, gene- 
rate the greatest amount of ammonia in the soil?" 

Chemistry would reply, — "When nearly all the seeds 
have become Jinn in the pods, but not dry." At this time 
the most forward pods will be dry, but the vines will still 
retain much of their greenness. Consequently, the seed 
portion of the crop will now contain nearly its maximum 
quantity^ of ammoniferous matter, while the vine j^ort ion will 
not yet have lost much of what belonged to it. This is the 
theory which science would present to the inquirer, inde- 
pendent of experiment, and based only upon the well-known 
character and composition of bean and pea crops generally, 
at the different stages of their growth. The experiments of 
the most successful pea-growers of the South confirm these 
simple deductions of science. 

506. If the vines are to be used as forage, they may be 
cut off close to the ground with sharp hoes, or still better 
with short stout scythes, and cured like clover hay. The 
curing is a somewhat difficult process. IMr. Ruffin remarks, 
that " at maturity of growth they should be pulled up, if 
planted in clusters (or perhaps cut by the scythe, if broad- 



308 B K A N S AND PEAS. 

cast ?), and put up in tall and slender shocks, supported by 
a small stake set in the ground, to remain till cured enough 
to stack, or to be put away in a house." Clover may be 
cured in the same way. 

507. Mr. Edmondston, of North Carolina, says: "As an 
article of forage or fodder, there is none superior to the pea- 
vine. Horses and cattle will eat it with avidity, and in pre- 
ference to any other kind of fodder. The difficulty of saving 
these vines has constituted the chief objection to their use. 
The writer believes that they can easily be saved, by cutting 
them oflF close to the ground with sharp hoes, in the month 
of September ; and then, having first provided forks and 
poles, plant the former in the ground in a straight line, and 
so place the poles upon the forks, that a common-sized 
man can clasp his hands over the poles [?'. e., they must 
be about 6 feet above the ground]. Place rails, with one 
end resting upon the ground, the other upon the pole, about 
6 or 8 inches apart, after the manner of a top-stack or fodder- 
house, as it is called, leaving both ends open, and upon these 
rails throw the vines, until they are about one foot deep ; 
throw over all some straw or grass, and a good supply of the 
best fodder for milch cows, or any other kind of stock, will 
be obtained." 

508. The Black-eye, and other early varieties of this pea, 
grow well in the valley counties of Virginia south of Au- 
gusta, at least well enough to give a good fallow ; and it is 
probable that they could soon be acclimated still flirther 
north, at least until a sufficient growth could be attained to 
make them well worthy of attention as a fallow crop. They 
grow well on both the clay and sandy soils of the south-west- 
ern part of the valley ; and in cases where soils are too poor 
to produce clover, the pea may be cultivated and turned 
down, until the soil is rendered sufficiently fertile for the 
improvement to be continued with clover. Another valuable 



QUESTIONS. 3C9 

purpose might be served by attention to this crop. There 
are cases in which farmers fail to get a stand of clover ; 
sometimes this occurs repeatedly for several years, until the 
land suffers seriously for want of a fallow crop. When such 
failures occur (and they are not unfrequent), a pea crop 
might be sown, and the land fallowed the next season. The 
Southei'u Pea could thus be made a valuable auxiliary to 
clover in enriching our lighter soils, and in rendering our 
stiff clays more mellow, as well as more fertile. 

509. The wheat drill may be used in planting peas. The 
quantity of seed can thus be regulated with accuracy; and in 
cases where the drills are thought to be too close, every alter- 
nate tube may be closed up, and the drills will then be double 
the width of those of wheat. 



QUESTIONS ON CHAPTER XXI. 

^§ 495, 496, 497. What are leguminous plants ? Examples? What 
valuable element do they contain in large quantities? What prote- 
ine body is found in them? What of the stalks? Product of the 
decay of proteine bodies? What if bean and pea crops are plowed 
down at the proper season ? What was once regarded as almost the 
only crop suitable for falloicing? 

498. Varieties for different latitudes? What suited to the Northern 
States? What extensively cultivated in the Southern States? Va- 
rieties of the Soulhern Pea?" 

499, 500. What is said of adapting themselves to climate? IIow 
may they be rendered earlier? Present limit of the Southern Pea? 
AVhich varieties are best adapted to the climate of Virginia? Which 
variety best adapted to table use ? Which to culture in the States 
farther south ? 

501, 502. What soiV best adapted to beans and peas? Influence 
of a very rich soil? What of the crop on poor soils? Where may 
the Southern Pea be especially available in restoring poor soils? 
What mineral manures does the crop require? What kind of plow- 
ing does this crop demand ? Why ? How does the crop fertilize the 
eoil? 



310 QUESTIONS. 

503, 504. Modes of Plantmg. — If cultivated for grain and forage, 
what should bo the mode of planting ? If the crop is to be plowed 
down for fallow, how may it be cultivated? First method given as 
practised in the Southern States? Second method? Method prac- 
tised in North Carolina for fallow crop ? Describe the fourth method. 
Why is this last method best where the peas are to be gathered? 
Why do they interfere so little with the corn among which they are 
planted ? 

505 — 509. 3Iodc of Gathering. — If the crop is intended chiefly for 
manure, when should it be plowed down? Value of the seeds as a 
fertilizer ? What question decides the time for plowing down ? How 
does chemistry settle this question? How does experiment settle 
it? How are the vines collected for forage ? How cured? Their 
value as forage ? Chief objection to their use ? Method of curing 
given by Mr, Edmondston, of North Carolina ? What varieties grow 
in the valley of Virginia? Of what crop may they prove an auxi- 
liary ? What instrument may be used in planting peas ? 



TOBACCO. 311 



CHAPTEE XXII. 

TOBACCO. 

510. This important Southern crop is becoming more and 
more widely cultivated, and the prospect of continued high 
prices is inducing many of our farmers to turn their atten- 
tion to its culture, in portions of Virginia and other States, 
both north and south of us, where, in former times, people 
have grown up to manhood without ever having seen a 
growing crop of tobacco. While so many new hands are 
thus engaging in its culture, it becomes important to have 
the leading points and principles involved in its management 
collected and set forth in a concise, systematic, and accessible 
form. The following discussion of this subject is the result, 
first, of the writer's personal observations of the methods 
pursued by some of the. most successful planters in Virginia 
and Kentucky; secondly, of information gathered from those 
familiar with the business; and thirdly, of gleanings from 
books and agricultural journals — especially the "Southern 
Planter." 

511. Climate. — Tobacco requires a long summer season 
to bring it to maturity. Hence, so far as our own country 
is concerned, the best tobacco can be cultivated only in the 
Southern States. Elevation has an influence somewhat 
similar to increase of latitude, not in the varying length of 
days, but in the lateness of Spring, and the early appearance 
of the cool nights and frosts of Autumn. This makes the 
culture of tobacco uncertain in the high and mountainous 
parts of Western Virginia, while a like risk is not felt in 



312 Ton A ceo. 

tlio same latitude further east, where the elevation is not so 
great. 

A variety, called the " Connecticut Seed-leaf," is begin- 
ning to be cultivated in considerable quantities in New 
England, and at present commands a good price. It requires 
a shorter season than the kinds cultivated farther south. 

512. Soil. — Tobacco will grow upon almost any good 
soil, when well prepared by thorough tillage, but that best 
adapted to its culture is a rich, dry loam, newly cleared 
and brought under cultivation. Although the light clay 
and sand loams, well manured, are the most reliable for 
making the finest qualities of tobacco, yet the clay soils — 
even the stiff clays of the limestone formation of the Valley 
of Virginia — produce excellent crops, but they require free 
applications of rich organic manures to render them suffi- 
ciently porous. The sandy loam, which has been drifted 
down from the mountain-gorges, along the northwest side of 
the valley, is well adapted to the growth of tobacco. 

513. Varieties. — " Owing to the great diversity of cli- 
mate and soil in Virginia, a corresponding change is pro- 
duced in the grades of tobacco raised throughout the State, 
yet she produces more valuable tobacco than any other State 
in the Union. The Orinoko and the Prior for manufac- 
turing, and the White Stem and Big Frederick for shipping, 
both in strips and stems, are the most profitable to the 
planter of all the various kinds rai.sed. Having had twenty 
years' experience in cultivating and manufacturing, and the 
la-it five years in selling the article, I am clearly of the 
o; inion that, on all lands suitable, the Orinoko is decidedly 
preferable for manufacturing, from the fact that it is the 
only kind that is sweet by nature, if ripe. It should be 
sun-cured, or as much so as the season and circumstances 
will admit. If thoroughly ripe it is much easier to be cured 
of the right color (I know of no object in nature that is 



TOBACCO. 313 

nearer that color than the land-terrapin, which, doubtless, is 
familiar to every planter), and it stands manufacturing better. 
If cut before being ripe, it chews bitter, its color is forced, 
and it will not hold it. The Prior is a good kind to culti- 
vate on all mountainous lands, as it stands the wind better 
than any other kind, being tough. For shipping purposes, 
I give the preference to the White Stem. It can be grown 
large and rich, is smooth and tough when cured, and loses 
less weight in the curing than any other kind." — W. H. Brown, 
^'Southern Planter," Jan., 1854. 

514. Plant-beds. — The climate, the soil, and the variety 
to be cultivated, being all favorably determined, the first and 
one of the most important ends to be attained, in order to 
insure success, is to secure an abundance of (/ood plants. To 
do this, the planter must look well to the preparation of his 
plant-beds. Of these he should have several, sown at dif- 
ferent periods, or one very large one, divided into several 
parts, to be sown at different times. He will thus secure 
a succession of plants, and can then avail himself of the 
most favorable season for " planting out." The condition of 
weather for the germination and growth may be very unfa- 
vorable after the planting of one bed, but more favorable for 
one planted earlier or later. To meet all the contingencies 
that may arise, and still secure an abundance of plants, 
enough of ground should be sown to produce (if all portions 
do well,) a large excess over what the crop to be raised will 
require. 

515. Preparation of beds. — The general practice is to 
burn the surface of the beds before planting. A warm and 
dry locality, exposed to the sun, and well protected against 
cold winds, is most suitable. A southern or south-eastern 
exposure should be selected, if possible, having a loose, rich 
soil. It should be well cleared of roots, stones, and every 
thing that might interfere with a proper tillage of the sur- 

27 



314 TOBACCO. 

face, or with the subsequent growth of the young plants. 
The burning process is then conducted by covering the bed 
entirely, or in part, with brush or logs previously collected, 
and igniting them at a time when they are dry enough to 
burn freely. The fuel should not be allowed to lie flat upon 
the ground while burning, but should be sustained upon 
cross logs placed beneath it. The whole bed need not be 
covered with fuel at one time ; because, when one portion 
has been subjected to the fire for an hour or two, the burning 
fuel may be removed to another portion, and thus the several 
parts be burnt in succession. Some important effects are 
produced by this roasting process. In the first place, any 
seeds of grass, weeds, &c., which may be in the soil, ready 
to spring up with the plants, are entirely or partially de- 
stroyed; and secondly, the condition of the soil is improved 
by burning (§ 424), and by the quantity of ashes left upon 
it. Beds should generally be burnt just before they are 
sown ; though, in some soils, it is better to burn and expose 
to frost a few weeks before planting. As soon as the surface 
is cool, guano, or some finely-pulverized manure rich in am- 
monia, and clear of seeds of every hind, should be freely 
applied, and the surface then be finely chopped up with the 
hoe, and smoothly raked. It will then be ready for the seed. 
"About two table-spoonsful of seed for every 100 square 
yards will be sufficient, and not too much. The seed are 
mixed with old ashes, and, to sow them regularly, it is best 
to sow one half over the bed, and the other half across the 
first sowing. It is then trodden, and thickly covered with 
brush." * The object of the covering with brush is to pro- 
tect the young and tender plants against frost and sudden 
changes of weather, and at the same time to admit the air, 
and the light and heat of the sun. The covering is removed 

* Wm. H. Jones, "Southern Planter" for November, 1854. 



T^OBACCO. 315 

when there is no longer danger of frost. One bed, at least, 
should be sown during the Winter, and others betimes in the 
Spring, so as to multiply the chances for an early supply of 
plants. Then, for later plants, another sowing should be 
made at a more advanced period in the Spring. 

Plants have been successfully grown by the application of 
guano abundantly, without the labor and expense of burning. 
. — (*S^ee '^Journal V. S. Agricultural Society," Vol. II., pp. 
.69, 70.) 

516. The fly is the great enemy of plant-beds. Various 
remedies have been tried for this evil, but none, perhaps, 
have succeeded better than the sprinkling of dry, fresh 
ashes, or newly-slacked lime, over the leaves of the young 
plants, by means of a sieve, or with the hand, as soon as the 
fly begins its depredations. 

An occasional application of guano and plaster, during the 
growth of the young plants, has the efi'ect generally of push- 
ing them forward, so that they spring up rapidly in spite of 
the fly. 

All weeds and grass should be pulled out of plant-beds as 
soon as they begin to make their appearance. To render the 
process of weeding convenient, and also to facilitate the 
drawing of plants, the beds are-frequently divided into smaller 
secondary beds, four or five feet wide, with narrow walks 
between them. 

517. Preparation of Soil. — This is a point of the very 
first importance in making a crop of tobacco. The soil must 
be both rich and mdlow. If the land is neidi/ cleared, all 
the undergi'owth must be well grubbed out, and everything 
be burnt upon the land, or removed fi-om the surface, which 
would impede the culture of the crop. This should be fol- 
lowed by two or three thorough coulterings, with strong 
teams, so as to break up as completely as possible all roots 
left in the soil. Hands should follow the coulter to cut out 



316 TOBACCO. 

and remove all the broken and exposed roots. The soil 
should be thoroughly plowed, and then listed and hilled in 
the best way, which the number of stumps present, and the 
general character of the surface will permit. Sometimes the 
hilling has to be done altogether with hoes, on account of 
the steepness or roughness of the ground. Such is often the 
case on the steep lands of those counties lying along the 
base of the Blue Ridge, and in many other places. At other 
times the soil may be first thrown up into beds or lists, and 
these be divided into hills with the hoes. 

New land is generally the best for tobacco. But in the 
best tobacco-growing sections, the land is nearly all cleared, 
except so much as is required to be kept in timber for 
fencing and fuel. The preparation of old land is here the 
matter of most importance. The point to be attained is to 
get a rich soil, deep and well pulverized. Tobacco requires 
an abundant supply of ammonia, as well as mineral matter, 
especially lime and potassa, with phosphoric and sulphuric 
acids. Hence, guano and rich stable or hog-pen manures, 
lime, ashes, plaster, and the phosphates, are all valuable fer- 
tilizers for this crop, unless they are already present abun- 
dantly in the soil. It has been shown that ammonia is not 
generally abundant in soils that have been frequently culti- 
vated without manure ; hence, old land usually requires an 
application of some form of ammoniferous manure, to secure 
a full crop of tobacco. A good clover or pea fallow may be 
plowed down in the Fall, and manured well and re-plowed 
in the Spring, with sub-soiling, where the land requires it; 
then, if necessary, in order to get it fully pulverized, let it 
be stirred with shovel-plows, and well harrowed. This will 
mingle the manure thoroughly with the soil, as well as reduce 
the soil itself to the desired condition. If manure is not 
abundant^ some guano should be mixed with it, and a smaller 



TOBACCO. 317 

quantity will then answer tlie purpose. All wet lands must 
be ^vcU drained for tobacco. 

518. Listing * and Hilling. — Listing here consists in 
throwing up small parallel ridges with the mould-board 
plow, at proper distances for the rows of tobacco. These 
ridges are often called " lists." The distance between the 
tops of these — or, in other words, the distance between the 
rows of tobacco — should be from 3 J to 4^ feet, varying 
with the soil and variety cultivated. The width should 
always be suflScient to allow the hands to pass between the 
rows, when the crop is fully grown, without danger of 
breaking the leaves. To secure uniformity of distance be- 
tween the lists, it is best to lay off the ground first with 
single furrows, at the required distance, and upon each one 
of these, as a central line, throw up the soil equally from 
both sides, with the mould-board plow, until all the soil has 
been thrown out from the middle of the intervening spaces. 
The lists may then be divided into sections, out of which 
the hills are to be formed. The hills should be about 3 feet 
apart in the rows. This distance can be regulated, with con- 
siderable uniformity, by running a shovel-plow across the 
lists at right angles, making cross-furrows three feet apart. 
The sections into which the lists, or ridges, are thus divided, 
are then heaped up in the form of sharply-peaked, conical 
hills, thus to remain until they are to receive the plants. 

519. The hilling serves several important purposes : (1) 
It elevates the plant, so as to prevent the points of its low- 
est leaves from reaching the ground so readily, and becoming 
soiled. (2) On soils which retain much water in wet sea- 

*• "Listing," in Soutliern agriculture, denotes: (1) The dividing 
of land into narrow strips by furrows, as in preparing it for plant- 
ing corn. (2) The same term is used to indicate the process of 
throwing the surface soil up into small parallel ridges, out of which 
the tobacco hills are afterwards formed. 
27* 



318 TOBACCO. 

sons, the plants are kept with a large portion of their roots 
above the water which settles along the furrows. But if 
wet seasons continue long, the crop is always injured, not- 
withstanding the elevation of the hills. (3) The air has 
more free circulation beneath the leaves when they become 
large, if the plants are thus elevated. 

520. Planting. — The season best suited for field plant- 
ing, in Vii'ginia, is from about the middle of May till about 
the middle of June, or later, in the southern part of the 
State. The process of planting can be carried on only when 
there is a considerable quantity of moisture in the hills, 
else just before there is a certain prospect of immediate rain; 
that is, just before or just after a rain. The hills are pre- 
pared to receive the plants, by having their conical tops cut 
ofi" with the hoe, and the flat surface thus formed, pressed 
down or struck with the lower face of the same instrument, 
so as to form a compact soil to receive the roots of the plant. 
While this operation is performed by one set of hands, 
others should be engaged in setting the plants. A careful 
man should draw the plants from the bed, which can be done 
with the hand alone, if the soil of the bed is loose and moist 3 
but if the bed has become somewhat hard, as often happens 
where there is much clay in the soil, the aid of a sharp flat 
instrument to pass under the roots may be necessary, as it is 
important to guard against bruising either the top or root 
of the young and tender plant. 

Some of the weaker hands take the plants in baskets, 
and, following those engaged in flattening the hills, drop a 
plant at each hill; while others follow with sharpened sticks 
or pegs, with which they make holes in the centres of the 
hills, to receive the roots. Care should be taken to have the 
root extend straight downward in the hole, and not doubled 
back upon itself: it is then more certain to grow, and to 
grow well. The plant should be inserted low enough to have 



TOBACCO. 319 

all the root completely covered, but not so low as to let the 
bud be below the surface. After the root has been inserted 
in the hill, the soil is firmly pressed around it. If the ground 
is not very moist, or if the sun is very hot, at the time of 
planting, a leaf of some kind, or a little handful of broken 
straw or chaff, should be laid over each plant till it has taken 
root. 

521. The same ground should be passed over at every 
good planting season, for the purpose of replanting. Some 
plants of the first setting will have died, while others will 
have been destroyed by cut-worms. To secure a plant to 
every hill, then, the replanting may have to be repeated 
several times. 

522. Another method of planting, differing a little from 
that just described, is said to be pursued by a very intelli- 
gent and successful planter in Buckingham county. His 
land is prepared and listed in the method just given; but 
instead of making hills, he lets the ridges (lists) stand as 
they are thrown up by the plow, until he is ready to plant. 
The tops of the lists are then flattened, and at the same time 
compressed, by running a one-horse roller along them from 
end to end. The roller is made sufficiently long to rest upon 
two lists at the same time, while the horse that draws it walks 
between. There is, moreover, an attachment to the roller 
for marking off the stations for the plants, at a uniform dis- 
tance. This consists of pegs projecting from the surface of 
the roller, and so situated that each one will make a hole for 
a plant at every revolution ; while those at the same end are 
just as far apart on the surface of the roller, as the plants 
are to be distant in the rows. If the diameter of the roller 
is near two feet, the circumference will be about six. Now 

,two pegs, placed on opposite sides of a roller of that size, 
would, during its revolutions, mark off spaces of three feet 
each ; that is, two spaces for every revolution. Each end 



o20 T O 15 A C C O. 

of the machine may thus be made to flatten the top of a list, 
and at the same time leave holes prepared to receive the 
plant. The difficulty of making a single peg always strike 
the centre of the list as it comes around, may be obviated 
by having several pegs near together, in a line running 
lengthwise. Some one of these will be certain to leave a 
hole near enough the middle of the list for the plant. , The 
plants are next dropped and set by hands following the 
roller. 

523. This method has the advantage of substituting cheap 
horse-labor for more expensive hand-labor ; but it may have 
more than compensating disadvantages. In rough or stumpy 
land, it would be impracticable. It omits the neat hoe- 
dressing applied in hilling. The plants are in rows in only 
one direction, and, consequently, cross-plowing cannot be 
done. Still, the plan is worthy of a fair trial, and on many 
fields may greatly economize labor. The substitution of 
horses or mules for men, is a point at which all farmers 
should aim, wherever such substitutions can be made. The 
hire of a first-class hand for one year, would buy a good 
mule ; while the expense of keeping the hand one year 
would feed the mule for two years. Then in many opera- 
tions the mule, with a little management, can be made to do 
the work of two or three good hands. 

524. Culture. — The two leading objects to be kept in 
view in the culture of tobacco, are the same as those men- 
tioned in connection with the culture of corn : (1) All weeds 
and grass must be kept down ; and (2) the ground must be 
kept mellow and well aired. The culture should be com- 
menced as soon after planting as possible, and kept up con- 
stantly until the plants are too large for its continuance. 
Within a week or two after planting, the soil on the surface 
of the hills may become crusted, especially in clay soils; 
also, grass and weeds may begin to make their first appear- 



TOBACCO. oJiL 

ance. In either case the hoe should be applied, to scrape 
down the surfaces of the hills. A clean, loose surface will 
thus be formed around the plants. This should be followed 
by a deep plowing, which should be made so close to the 
rows as to cut down a considerable portion of the hills, the 
mould being thrown out into the spaces between the rows. 
Guano, or a mixture of guano and salt, should then be ap- 
plied. By a subsequent plowing within a week or two, the 
soil should be thrown up again to the rows, and the hills 
again dressed up with the hoes. The kind of plow used 
must be determined by the character and condition of the 
soil. To a firm soil, the coulter should be first applied to as 
great a depth as possible ; then the shovel, or small mould- 
board, for throwing the earth to and from the hills. In short, 
the best means should be adopted for accomplishing the two 
objects above mentioned. 

525. Priming and Topping. — When the plant has 
grown to the height of two or three feet, a round bud will 
make its appearance in the centre of the plant. This is the 
fiower-hud, and is called the " button" in some parts of Vir- 
ginia. At this period of growth, some of the lower leaves 
should be pulled oif, so as to leave the stalk naked for five or 
six inches above the ground. The stripping of these lower 
leaves is called '' priming." At the same time that the prim- 
ing is done, the flower-bud is broken or nipped off with the 
thumb and finger. If the plant is sufficiently large, it may 
be topped before the flower-bud appears, by nipping out the 
central leaf-bud. '' There is great difierence of opinion aa 
to the proper height of topping. From 8 to 20 leaves are 
recommended — the latter for manufacturing. If the tobacco 
is pretty forward and the land rich, at first, prime off just 
enough of leaves to hill up the tobacco weir, and top to 12 
or 14 leaves. Continue to top to 12 leaves until 1st of Au- 
gust, then top to 10 until middle of August, and from that 



322 TOBACCO. 

time until 1st of September top to 8, afterwards to 6." * If 
the topping were omitted, the flower-bud would soon be de- 
veloped into a branching top, full of clusters of flowers, from 
which the seeds are afterwards produced. 

526. SucKERiNG. — Soon after the topping is done, the 
axillary buds at the bases of the leaves begin to grow rapidly, 
and, if let alone, form branches of the main stalk. They 
are called " suckers," and must be broken out as soon as 
they are large enough to be caught with the thumb and 
finger. This process has to be repeated from time to time, 
as new suckers make their appearance. Meantime the green 
worm will have commenced its ravages, and must be care- 
fully picked off" and destroyed ; otherwise, it will soon dis- 
figure and greatly injure the crop. 

527. The p^iilosophy of priming, topping, and suckering 
is easily understood when we refer back to what has already 
been said (Chap. XI) on the physiology of plants. All parts 
of the plant are designed to aid in its mature growth, and 
ultimate production of seeds. As the period approaches for 
maturing the seeds, nearly all the vital energy of the various 
organs seems to be directed towards, and expended upon 
them. If the first flower-bud is removed, the natural vigor 
of the plant is not destroyed, but only diverted towards the 
leaves and axillary buds, strengthening the former, and caus- 
ing the latter to spring up as suckers. But when the suckers 
are removed, the whole vigor of the plant is concentrated in 
the remaining leaves. A choice of the most perfect leaves 
is made by " priming off"" those nearest the earth, and which 
not only would not themselves attain a vigorous growth, but 
would exclude the air and light too much from the middle 
leaves of the plants, which are always the most vigorous. 
The number of leaves left in topping is determined in part 

* Southern Planter, Nov. 1854. 



TOBACCO. • 323 

by the apparent strengtli of the plant, and in part by the 
length of time it has for maturing its leaves. The more for- 
ward plants have a longer season of growth after topping, 
and can hence bear a greater number of leaves j while the 
later ones must be topped lower. 

528. Cutting. — The maturity of the plant, and conse- 
quent fitness for cutting, is indicated by the points and edges 
of the leaves curling downward, the leaf becoming thick and 
brittle, and its surface assuming a yellowish spotted (piebald) 
appearance in some varieties, and on some soils, especially 
new land; and a fine glossy appearance in others. At this 
stage, the plant contains more of those ingredients which 
subsequently give value to it, than at any period either 
earlier or later. It should then be cut, and not till then, 
unless it is becoming fired,* or is in immediate danger from 
frost. The cutting consists in splitting the stalk with a 
sharp, thin-bladed knife, down nearly to the lowest leaf, and 
then cutting it off just below this leaf. As the plants are 
cut, they are inverted between the hills, and allowed to re- 
main in that position a few hours, until they are sufficiently 
wilted to be handled without being broken. They are then 
collected and placed (8 or 10 together) upon sticks, and 
hung upon scaffolds in the open air, or in the tobacco barn. 

529. Curing. — The process of curing is a matter of the 
highest importance. On it depends, to a very great extent, 
the market value of the crop. It should, therefore, be at- 
tended to with great care. The modes adopted vary some- 
what with the end for which the crop is designed, " To- 
bacco for manufacturing purposes should be exposed to the 
air on scaffolds; and if ripe and sun-cured, it will have that 

* The "Black Fire" is a disease which is often very destructive 
to Ihe tobacco crop. It produces decayed spots over the leaves. A 
mixture of common salt with guano is recommended as a preventive. 
—Southern Planter, May, 1 858. 



324 • T O R A c c o . 

sweet, aromatic flavor so peculiar to good tobacco. * * * 
After cutting, it should be carried to the scaffolds and hung, 
about 8 plants to the stick, and closed on the scaffolds for 
the purpose of sweating, by which process the green color is 
expelled, and the tobacco becomes yellow, which is far pre- 
ferable." * It should then be removed to the barn, to be 
fully cured by firing. " If time will allow, and the weather 
is not threatening, I prefer housing the tobacco without scaf- 
folding. It will yellow as well, crowded in the barn, as on 
the scaffold ; and all danger of injury from rain is avoided., 
as well as the loss of some from the effects of the sun. * * * 
It is carried from the field, crowded as closely as possible on 
the tiers, and permitted to remain from 6 to 8 days, or longer, 
until it is yellowed sufficiently ; then it should be opened, 
and the sticks arranged in the barn for firing. The sticks 
should be placed from G to 8 inches apart, and may be placed 
a little closer in the roof than in the body of the barn.""!" 

530. Chemistry. — During the process of curing, tobacco 
undergoes important chemical changes. Its peculiar pro- 
perties are owing to the presence of several remarkable com- 
pounds, of which one called " nicotine," and another called 
" nicotianine," are most important. Nicotine is an alkaline 
substance, and has the form of an oily liquid when separated 
from other compounds. In its concentrated form, it is a 
most deadly poison ; but when taken in the dilute condition 
in which it reaches the stomach in chewing, or the lungs in 
smoking "the weed," its effects are greatly modified. The 
quantity of nicotine varies in the different qualities of to- 
bacco cultivated in the same region, and still more does it 
vary in that cultivated in different countries. The Havana 
has about 2 per cent of nicotine, hence its mildness. Vir- 
ginia (best manufacturing) tobacco has 5 or 6 per cent, 



* T. D. Edmunds. f Wm. H. Jones, of Mecklenburg. 



TOBACCO. 325 

while the stronger varieties have about 7 per cent. The 
French tobacco has from 3 to 8 per cent of nicotine, accord- 
ing to the region in which it grows. Nicotlanine is a more 
volatile substance than nicotine, and is more odoriferous. 
The pleasant odor of good tobacco is due to this compound 
chiefly. 

531. The nicotine and nicotianine do not exist in the green 
leaf, but are formed during the curing of the tobacco, from 
substances already in the plant in variable quantities. If 
the leaves are dried very rapidly, these compounds are not 
fully formed ; and if the heat is raised too high in firing, 
they may both disappear to some extent, by being either 
volatilized or decomposed. They both contain nitrogen, and, 
like all other compounds containing that element, are readily 
decomposed. Hence the firing should be commenced at a 
low temperature, which should be gradually increased, and 
may be advantageously suspended at night. The tempera- 
ture should never rise above 120°. 

532. Tobacco-barns should be closely planked, or in some 
way made close, having windows for ventilation, which may 
be opened or closed at pleasure. Smaller, and hence safer 
fires, will be sufficient in such houses. Curing yellow to- 
bacco with cliarcoal at a high temperature, kept up day and 
night, is recommended.* 

" It is best to fire all grades of shi]/2)ing tobacco, and cure 
it a dark nutmeg color. * * From 24 to 36 hours after cut- 
ting, if the tobacco is ripe — if not, from 36 to 48 hours, 
according to the weather — seems to be about the right time 
to commence firing. Begin with small fires, and bring the 
tobacco to a proper state, and then increase the fires." f 

533. Stripping, &c. — After the tobacco has been fully 

* See Southern Planter, Oct. 1858. 
f Wm. H. Brown, Richmond. 
28 



32G TOBACCO. 

cured, the nest step is to strip the leaves from the stalks, 
and tie them up in little bundles ('' hands,") to be pressed 
(" prized,") into hogsheads for market. The two points 
requiring most attention in stripping are, first, to have the 
tobacco in proper ''order;" and, secondly, to assort carefully, 
so as to separate the different qualities. 

534. The tobacco is in " order" when the leaf, or rather 
the blade of the leaf, is sufficiently moist to be pliant, and 
yet the stems dry enough to break off readily from the stalk. 
This condition can be secured only in the beginning of a 
spell of damp weather. After the weather has continued 
damp for some little time, the moisture penetrates the stems, 
as well as the thinner parts of the leaves, making them too 
tough to be easily broken from the stalks, and rendering 
them liable to mould when wrapped together, or when the 
tobacco is laid down " in bulk." If the stems have thus 
become pliant, the tobacco is in " too high order," and must 
be thoroughly dried, and allowed to come in order again 
before the stripping can be done. 

535. A large quantity may be kept in order for stripping, 
by packing it down when in the proper condition, upon an 
elevated platform extended along one side of the barn. This 
is called '' bulking." The tops of the plants must be lapped 
over each other in the middle of the pile, the lower end of 
the stalks being turned outward. The whole mass must 
then be covered up with straw, or something else, which will 
preserve it in order until it can be conveniently stripped, 
which is generally at times when the weather is unfavorable 
for out-door work. 

53G. The business of assoiiinr/ requires both care and 
judgment. It should, therefore, be the business of the most 
experienced and trustworthy hands. It is accomplished 
chiefly during the process of stripping, but may be made 
more complete by the hands engaged in tying, attending 



QUESTIONS. 327 

properly to the sorting out of such leaves as do not properly 
belong to the quality upon which they are engaged. The 
number of grades or qualities must be determined by the 
purpose for which the crop is designed. Where the only 
object is to make the dark shipping tobacco, the best leaves 
are assorted, according to size and quality, into first and 
second quality of " leaf;" while the lower leaves of the stalks, 
together with any othei-s that may be injured or ragged, form 
first and second qualities of '' lugs." 

If the crop is designed for the manufacturer, the color, as 
well as other qualities, must be taken into account. The 
dark and yellow colors must be first separated into two general 
classes, and then each of these again assorted according to 
their several 'Equalities." 

537. When the assorting and tying have been completed, 
the bundles should be " bulked down," unless the stems are 
found to contain so much moisture as to be in danger of 
moulding. It should then be hung up on the sticks, and 
dried. It is always thoroughly dried before prizing. Then, 
at the first favorable time before prizing, it should be again 
packed down in bulk. The bundles should be carefully 
straightened in packing down ; and, when it is aftei-wards 
transferred to the hogsheads, the same, or still greater care, 
should be taken to have every leaf straight, and in its proper 
place. The hogsheads usually contain about 1300 or 1400 
pounds. 

The price of tobacco depends very much upon the skill 
icith which it has been cured, and tlie care bestowed upon the 
assorting, tying, and subsequent handling. 

QUESTIONS ON CHAPTER XXII. 
§•510, 511. What is said of tlie extension of the culture of To- 
bacco? What citma^fi is best suited to this crop? Wliy? Influence 
of elevation? 



328 QUESTIONS. 

512. Soil best adapted to tobacco ? What of the clay soils ? What 
of the drift deposits in the valley? 

513. What gives rise to variety o^ grades in tobacco? Variety 
best for manufacturing? For shipping? To what lands is the Prior 
adapted ? 

514-51 G. Why do Plant-beds require special attention? How is a 
succession of plants to be secured ? Why important ? The general 
practice in the preparation of beds ? Locality selected ? Preparation 
of the ground ? How is the burning conducted ? Effects of burning? 
When should beds be burned? What is said of the application of 
guano? How are the seed prepared? How planted? Time of 
planting? Growing of plants without burning? Great enemy of 
plant-beds? lleniedy? AVhat application should be made during 
the growth of the plants? Attention to weeding? 

617, 518. What is especially required in Xhe preparation of the soil? 
How is new ground to be managed ? How is the hilling performed ? 
Preparation of old land ? What fertilizers are especially required 
by tobacco ? What fallow-crops make a good preparation for tobacco ? 
How must wet lands be treated ? V/hat is meant by listing tobacco 
land ? Proper distance between the rows ? How is uniformity of 
distance secured ? Dist,ance between the hills ? 

519. nUling? Fii'st purpose served by hills ? Second? Third? 

520. Planting season? How are the hills prepared to receive the 
plants? Describe the process of planting. 

521. 522. What of replanting ? What method of planting without 
hilling is described ? Detail the process. Advantage of this method ? 

524. Leading objects to be observed in culture of tobacco ? When 
commenced? How conducted? 

525-527. When are priming and topping commenced ? What is 
priming? What is topping? What determines the number of leaves 
to be left ? What renders suchering necessary ? How performed ? 
Jixplain the philosophy of pruning, topping, and suckering. 

528, 529. When is the plant fit for cutting? How indicated ? Why 
is it then most valuable? How is the cutting performed ? What is 
next to be done ? Why is the process of curing a matter of great 
importance? How is manufacturing-tobacco cured? 

630-532. What chemical changes take place in the curing of to- 
bacco ? What substances are formed in the tobacco? The proper- 
ties of these ? Quantity of Nicotine in difiFerent varieties ? Influence 



QUESTIONS. 329 

of drying the leaves very rapidly? Effects of too high temperature? 
Advantage of closely-planked barns? Curing with charcoal? How 
should shipping tobacco be fired ? 

533-537. In what does the stripping of tobacco consist? Two 
points to be observed? When is tobacco "in order"? When should 
it be laid down in bulk ? How may a large quantity be kept in 
order? What does the business of assorting require? AVhat points 
decide the quality of tobacco? What process follows stripping and 
tying ? On what does the price of tobacco very much depend ? 



28^ 



oO COTTON, 



CHAPTEK XXIIl. 

COTTON. 



538. The following remarks on the planting and culture 
of cotton are compiled chiefly from the " Cotton Planter's 
Manual" (J.A.Turner). All the leading points to be 
observed in the management of this great Southern crop 
are believed to be here presented. Modifications, of course, 
must be made to suit differences in soil, climate, &c. Those 
who wish to investigate the subject fully are referred to the 
valuable "Manual" above mentioned, and to Southern Agri- 
cultural Journals. 

539. Kind or Soil. — "The first inquiry which presents 
itself is, to know what are the peculiarities of those soils 
which suit the growth and maturity of cotton. Experience 
is, perhaps, the safest and most reliable test, in the settle- 
ment of this question — and it is now pretty universally con- 
ceded, that- our best cotton lands are those which are of deep 
and soft mold, a sort of medium between the sandy and 
spongy, and those soils which are hard and close — those 
which are penetrated by the warming rays of the sun, im- 
bibing readily the stimulating gases of the atmosphere, and 
which allow the excess of rain-water to settle so deep into 
the earth, as to lie at a harmless distance below the roots of 
the young plant. These are the properties of soil needful to 
the vigorous growth and early maturity of the cotton plnnt; 
and the knowledge of this fact is of great, and perhaps I 
might add, indispensable importance, to its successful culti- 
vation. For though we may not find, and indeed it is very 
improbable that we should often find, all these essentials in 



COTTON. 331 

the selection of a farm, yet by the aid of the plow, the hoe, 
and the spade, and the incorporation of foreign substances, 
we may remedy many defects, and supply many of the pecu- 
liar demands of this plant. 

540. Preparation of Soil. — ''The best and most im- 
portant part of the work in cotton making, consists in a 
judicious and proper preparation of the soil for planting. 
It is difficult to say, in all cases, and in the varied condition 
in which lands are found, and the diversity of soils, what 
the process of preparation should be ; but we lay down gene- 
ral principles for our government, and results to be obtained, 
and leave the planters to the selection of the best means at 
command for their accomplishment. All lands for cotton 
ought, before the crop is planted, to be broken deep, close, 
and soft ; and this to be done long enough before planting 
to allow the rains gently to settle them. It is the most 
common and perhaps the best plan, to prepare all lands in- 
tended for cotton, in beds made by the turning-plow; and in 
flat and wet lands, sometimes an additional elevation ought 
to be given, by drawing up the beds with the hoe. I think, 
in this work, we have often followed too much the example 
of our neighbor, and have looked too little to reason, in the 
indiscriminate bedding and high elevation of all lands. I 
am the advocate of deep, soft beds, made by very thorough 
and close plowing, but cannot consent to the necessity or 
benefit of elevating much lands which are warm and dry, 
and which are not subject to inundations from excessive 
rains. For the convenience of culture, I would have the 
young cotton stand on a slight elevation ; but when the con- 
dition of the land did not require it, I would not give it 
more." — Col. Chambers's Essay, pp. 11—13.) 

541. Manures. — "Every kind of compost, green crops 
turned in, cotton-seed, and even naked leaves listed and left 
to rot, improve this crop. When planted on cotton-seed, 



332 COTTON. 

and sometimes on strong stable manure, it is more difficult 
to retain a stand, owing, probably, to the over-stimulus of 
these strong manures. So, on leaves, unless well-rotted, the 
cotton will long continue to die, in consequence of the leaves 
decaying away, and exposing the root too much to sun and 
rain. These difficulties maybe avoided by a little pains; 
and by no means justify the opinion entertained by some, 
that cotton should never be planted on freshly-manured land. 
The only question is the cost of the manure. A great deal 
may be made on every plantation, without much trouble or 
expense, by keeping the stables and stable-yard, hog and 
cow-pens, well supplied with leaves and straw; and also from 
pens of corn-cobs, sweepings from negro and fowl-house 
yards, and rank weeds that spring up about them, collected 
together, and left to rot. Whenever the business is carried 
further, and a regular force is detached to make manure at 
all seasons, and entirely left out from the crop, it becomes 
the owner to enter into a close calculation of the cost and 
profits. In many agricultural operations, such a course the 
experience of all countries has proved to be profitable; but 
these operations partake more of the farming and gardening, 
than planting character ; and whether the same method will 
do for the extensive planting of short-staple cotton, remains, 
in the opinion of your Committee, yet to be tested. If any- 
thing like an average of past prices can be maintained, it is 
certain that more can be made by planting largely than by 
making manure as a crop. If, however, prices continue to 
fall, and the growing of cotton be confined to a few rich 
spots — those susceptible of high manuring — then our whole 
system must be changed, our crops must be curtailed, and, 
staple-labor losing its past value, the comparative value of a 
cotton and manure crop will preponderate in favor of the 
latter. As a substitute for manuring on a large scale, rest- 
ing and rotation of crops is resorted to. In our right level 



COTTON. 333 

land, the practice of resting cannot be too highly recom- 
mended ; and, by a judicious course, such as resting two, 
and planting two, or at most three years, our lands may not 
only be kept up forever, but absolutely improved. From 
rotation of crops, but little is done for cotton. After small 
grain — whether from the exhausting nature of that crop, on 
light lands, or because the stubble keeps the ground rough 
and porous — cotton will not do well. After corn it is difficult 
to tend, as, from our usual manner of cultivating corn, grass 
is always left in full possession of the field. It does best 
after cotton, or after a year's rest. Rest is the grand re- 
storer, and the rotation chiefly required in the cultivation of 
cotton." — Gov. Hammond's Report, p. 27. 

542. Application or Manures. — Dr. Cloud, after va- 
rious experiments, says : " I determined upon a new mode 
of application entirely, which consisted in spreading all the 
manure used broadcast. This was done by hauling the ma- 
nure out on the land, and depositing it in heap rows, say 
thirty feet apart, and the heaps thirty feet apart in the rows, 
with ten bushels of manure in each heap. The cotton-rows 
being first laid, the manure was spread broadcast, and the 
land bedded out. On or about the 10th of April, the cotton- 
seeds were planted after a spacer, by which the hills are 
regulated precisely as desired. The result was a perfect 
stand, with the cotton healthy, and all of the same age. 
There is no difficulty in understanding the difference here 
in favor of broadcasting the manure, and in bedding out the 
rows. It is not deposited a half-gallon in a place, but is in- 
corporated evenly throughout all the soil. The consequence 
is, that however rich the manure may be in alkaline matter, 
its thorough incorporation with the soil, so quickly and 
effectually dilutes it, as to render it entirely innoxious to 
young cotton. There was no part of the experiment that 
gave me so much satisfaction as this. Every planter knows 



334: COTTON. 

the value of a first uniform and perfect stand. I use tlie 
term perfect, because, by the use of the spacer, I approxi- 
mate nearer a perfect stand than it is possible to accomplisli 
by any other process." — Dr. CloutVs Exjicrimcnts, p. 72. 

54:0. Planting. — '' The distance to be given is the next 
inquiry to be considered. This is a very important object, 
and one upon which we are very dependent for success ; and 
yet it must be varied very much by circumstances, some of 
which are beyond our knowledge or control. The general 
principle may be stated, and then our best judgment must 
guide us in its ajiplication. 

" When the crop is at maturity, the branches of the stalks 
ought slightly to interlock every way. We cannot, there- 
fore, do better in planting, than make an estimate of the 
probable average to which the weed will grow, dependent, 
of course, upon the vicissitudes of the seasons. It would, 
therefore, be vain to attempt to be more specific in direc- 
tions, which must be varied always to suit the varied cha- 
racter of the soil. This whole question, then, is to be set- 
tled upon the principle already stated. The planting should 
be in drills, chiefly because of the difficulty of obtaining 
good stands in hills ; and I would add, for the information 
of those who may be without experience, that in the com- 
mon medium lands of the country, these rows ought ordina- 
rily to be about five feet apart, and the stalks in the drill 
should be thinned, so as to stand from fifteen to twenty 
inches from each other. The width of the rows, and the 
distance in the drill, may be increased upon better lands; 
and in some cases of very thin lands, it may fall a little 
below the distances designated. I do not regard it as a 
matter of indispensable importrnce, but should decidedly 
prefer that the rows should run in such direction as to give 
the plant the largest benefit of the sun, from early morn to 
its setting. The cotton is decidedly a sun plant. 



COTTON. 3^5 

544. The Mode of Planting. — " Here -we have many 
plans, all setting up claims to some peculiar merit. With 
the preparation which I have indicated, it would hardly be 
necessary to stop to discuss the relative merits of these 
modes, or seek to do more for the accomplishment of our 
purpose than to select some one, which we know to answer 
well. I therefore advise the use of some small and very 
narrow plow for the opening furrow. This should be run in 
the centre of the bed, opening a straight furrow of uniform 
size and depth. In this the seed should be strewed by some 
careful hand, scattering them uniformly along the furrow, 
just thick enough to secure a good stand the whole length 
of the row. These I would cover with a board, made of 
some hard wood, an inch or an inch and a half thick, about 
eight inches broad, and thirty inches long, beveled on the 
lower edge so as to make it sharp, slightly notched in the 
middle so as to straddle the row, with a hole bored in the 
centre one inch from the upper edge, and screwed on the 
foot of a common shovel or scooter-plow stock. This wooden 
scraper and coverer, when drawn over the row, covers the 
seed nicely, leaving a slight elevation to prevent the settling 
of water, and dresses the whole surface of the bed neatly for 
the space of fifteen inches on each side of the drill. Thus 
all clods or obstructions arc removed, and a clean space is 
left wide enough for the passage of the plow in the first 
working between the young cotton and the rough land. This 
is an advantage of much importance with a crop so tender 
and small as cotton at this stage. 

545. Culture. — "As soon as the young cotton is up to a 
good stand, and the third and fourth leaves begin to appear, 
the operation may commence. In lands which are smooth 
and soft, I incline to the opinion, that the hoes should pre- 
cede the plows, chopping into bunches, passing very rapidly 
on, and let a careful plow-man follow on each side of the 



33G COTTON. 

dilil, throwing a little liylit dirt into the spaces made by the 
hoe, and a little also about the roots of the cotton, covering, 
and leaving covered, all small grass which may have sprung 
up. This is, indeed, the merit claimed for the operation 
that, after the hoes have passed, the plows come on and 
effectually cover and destroy the coat of young grass then 
up. This is known to practical planters to be the crop of 
grass which escapes the hoe, and does mischief to the cotton. 
But when the land is so rough as to endanger the covering 
of the cotton with the plow, the operation must be reversed, 
and the hoes follow the plows. All that is now proposed to 
be done is a very rapid superficial working, reducing the 
crop to bunches, soon to pass over and return again, for a 
more cai'eful operation. This should be done as soon as 
possible, as will be indicated by the necessities of the case. 
The grass and the weeds must be kept down, and the stand 
of cotton reduced. At this first working, unless in lands 
already very soft, I should advise the siding to be close, and 
to be done with some plow which would break and loosen 
the earth deep about the roots of the young plant. Others 
may theorize as they choose, but with a plant sending out a 
tap-root, upon which it so much relies, and striking so deep 
into the earth, as that of cotton, I shall insist upon its 
accommodation, by providing a soft, dee]), mellow bed, into 
which these roots may penetrate. 

546. " In the second working, the plows should in all 
curies go before the hoes, and in all lands at all tenacious or 
hard, let the work be deep and close again, and the middle 
of the rows also be well broken up at this time. Now the 
hoes have an important and delicate duty to perform. The 
cotton is to be reduced nearly to a stand, though it is now 
rather early to be fully reduced. It is, perhaps, best to 
leave two stalks where one is intended to grow. The young 
stalk is very tender, and easily injured by bruises and skins 



COTTON. 337 

from rough and careless work, and it is much better to aid a 
little sometimes with the hand in thinning, than to spoil a 
good stand by bruises from the hoe. The cut-worm and the 
louse are charged with many sins, which ought to be put 
down to careless working at this critical stage of the crop. 
The distance to be given I have before stated, and, in the 
first operation of bunching, this ought to be looked to, and 
the spaces regulated accordingly. At this second passing 
over, the hoes must return a little soft dirt to the foot of the 
stalk, leaving it clean and supported. If this work is well 
done, the weed will grow on, without any necessity for fur- 
ther attention for some twenty days or three veeks, when 
the plow should return again. At this time, some plow 
should be used next the cotton, which will tumble the soft 
earth about the root, covering the small young grass which 
may have sprung up since the last working, but the plowing 
should be less close, and shallower than the former working. 
547. " The hoes have much to do in the culture of this 
crop, and must be prepared to devote pretty much all their 
time to it, constantly passing over, and perfecting that which 
cannot be done with the plows, by thinning out surplus 
stalks, cleaning away remaining bunches of grass, stirring 
about the roots of the plant, and, if need be, adding a little 
earth to them. It is difficult, in a treatise of this sort, to 
say how often, and in what manner, this crop should always 
be worked, when the character of the seasons, and the dif- 
ference in the land, must have necessarily so much to do in 
settling this question. The general rule must be, to keep 
the earth loose and well stirred ; the early workings to be 
deep and close; and as the crop comes on, and the fruit 
begins to appear, let these workings be less close, and shal- 
lower, keeping the soil soft and clean. It is of great import- 
ance to work this crop late, and it should not cease until the 
branches lock, or the cotton begins to open. I do not con- 
29 



338 COTTON. 

sider tliat it is necessary to pile the eartli in large quantities 
about the roots of the cotton, but think the tendency of all 
the workings should be to increase the quantity. 

548. Selection of Seed. — " The selection of seed is an 
interest not to be disregarded. We have been humbugged 
a great deal by dealers and speculators in this article, yet we 
would greatly err to conclude that no improvement could be 
made. We should, however, save ourselves from this sort 
of imposition, and improve our own seed, by going into the 
field, and picking each year from some of the best-formed 
and best-bearing stalks, and thus keep up the improvemfent. 
Great benefits may often be derived by changes of seed in 
the same neighborhood, from difi"erences of soil, and occa- 
sional changes from a distant and different climate, may be 
made to great advantage. 

549. Picking. — " The picking of cotton should commence 
just as soon as the hands can be at all profitably employed — r 
say as soon as forty or fifty pounds to the hand can be gath- 
ered. It is of great importance, not only to the success of 
the work, but to the complexion and character of the staple, 
to keep well up with this work, so that, as far as possible, it 
may be saved without exposure to rain. The embarrass- 
ments to picking when once behind, and a storm or heavy 
rain shall intervene, mingling it with the leaf, and tangling 
in the burr, are just as great as to get behind in the cultiva- 
tion of the crop, when much additional labor will be required 
to accomplish the same object. 

" In the early pickings, when the seeds are green, some 
sunning is indispensably necessary; but, after some maturity 
and dryness, very little will be required. This must be de- 
termined very much by circumstances; but dew or rain-water 
should always be removed by drying upon the scaffold, before 
the cotton is bulked in the house. AVith proper care and 
attention, great improvement may be given to the complexion 



COTTON. 339 

of the staple by a little heating in the bulk, extracting the 
oil from the seed, and imparting a slight cream to the color. 
This process, however, must be conducted with great caution 
and care, lest the heating proceed too far, and injury be 
done. It is easily checked by stirring and exposure to the 
air. It is an advantage to all cotton to lie in the bulk before 
ginning, and we doubtless often lose much of this benefit 
for want of sufficient house-room. Indeed, I think it a very 
common error in our plantation arrangements, not to build 
houses for this special object. The cotton, when ginned, 
ought to be so dry that the seed will crack when pressed 
between the teeth. It is often ginned wetter, but just as 
often the cotton samples blue. A gin should be used which 
will neither cut nor nap the cotton, but send out the fibre 
straight and smooth, so that when the samples are drawn, 
they will have the appearance of having been carded. This 
is greatly promoted by the largely increased number of 
brushes now added by the best manufacturers. 

550. Packing. — " The packing should be in square bales; 
and, without reference to freight, or any of these mere inci- 
dental influences, I think the weight of the bale should be 
fixed at about four hundred or four hundred and twenty-five 
pounds — to be in two breadths of wide bagging, pressed 
until the side-scams are well closed, or a little lapped, and 
then secured with six good ropes, the heads neatly sewed 
in ; so that, when complete, and turned out of the press, no 
cotton should be seen exposed. These packages should be 
nearly square, for the greater beauty of the bales, but, still 
more, for the greater convenience with which they may be 
handled and shipped, saving the necessity for tearing the 
bags, and giving a better guarantee that they will reach a 
distant market in good order." — Col. Chambers's Essay, pp. 

16-20. 



340 QUESTIONS. 

551. Remarh. — I do not pretend to endorse every position 
taken, and opinion expressed, in the above comj)ilation. The 
writers are intelligent and responsible men, and have had 
personal experience in the matters about which they write. 
I have never lived in a cotton-growing region ; and, there- 
fore, have had but little opportunity of personal observation 
in the culture of this important crop. But, in addition, to 
what has been given, I will venture a suggestion, based upon 
my general knowledge of the cultivation of the soil. One 
of the writers quoted speaks of rest, as '' the grand restorer, 
and the rotation chiefly required in the cultivation of cot- 
ton." Now I venture to suggest a ^^ea fallow, with gypsum 
and ashes, as probably much superior to "rest" for any soil. 
"Rest" can never restore to land what the crops are every 
year carrying away; and unless the rest is emploijcd in the 
production of something which will collect organic fertility 
from the air, and improve the chemical condition of the 
mineral matter, which needs elaboration, it can certainly do 
but little for the ultimate improvement of the land. 



QUESTIONS ON CHAPTER XXIII. 

§ 538, 539. Is the proper culture of Cotton the same for all locali- 
ties ? Soil best adapted to this crop ? Why ? 

540 — 542. What of preparation of soil ? How should the soil be 
broken up? Why should cotton be planted on beds? Kind of ma- 
nures suited to cotton? How is the cost of manure to be attended 
to ? Modes of applying manure ? 

543, 544. How is the distance of planting determined ? How should 
the planting be conducted ? AVidth of the rows and distance in the 
drill ? Mode of planting given ? 

545 — 548. First step in the c!/Z<?<re of the crop ? Use of the plow ? 
When should the hoe follow the plow? Why should more stalks be 



QUESTIONS. 341 

left at the first thinning than are intended to grow ? How long should 
the culture continue? Why is the selection of seed important? 

549. When should the picking of cotton commence? When is 
sunning necessary? Influence of having the cotton well cui'ed? 
AVhat should be the condition of cotton when ginned? What kind 
of gin should be used ? Why ? 

550, 551. In what kind of bales should cotton he packed? Weight 
of the bales? Why should the bales be square? Suggestion given 
as to fallowing for cotton ? 



29* 



i 12 ROTATION Of C II r S , 



CH AFTER XXIV. 

ROTATION OF CROPS, 

552. By "rotation of crops" we denote the cnltivatioii of 
different kinds of crops itpon the same field, in a uniform 
order of succession. This requires a systematic division of 
the land, as well as a systematic order of culture. For ex- 
ample, if corn, oats, wheat, and clover are the crops to he 
cultivated every year upon a farm, there must be at least one 
field, or one division of a field, for each. Then, if they are 
to be cultivated by a regular system of " rotation," they must 
succeed each other in the same order, on each of the several 
divisions of land. Thus, let A, B, C, and D represent the 
four fields, of which we will suppose, for the first year, A 
to be in clover, B in wheat, C in oats, and D in corn. The 
second year we may plant corn on the clover-sod of A, and, 
having sown clover-seed the first 3-ear on the wheat in B, we 
now have clover the second year on B. We sow wheat on 
the oat stubble of G, and oats on the corn stubble of D. The 
tJiird year A is to be in oats, B in corn, C in clover, and I) 
in wheat. The fourth year A is in wheat, B in oats, C in 
corn, and D in clover. In the fifth year we return again to 
the same order with which we set out on the first year, 
namely, A in clover, B in wheat, C in oats, D in corn; and 
so the order during the sixth, seventh, and eighth years, 
Avould be the same as that of the second, third, and fourth. 
Thus, these four crops may be made to follow each other in 
the same order, over a system of fields, fur any number of 
years. This will serve as an example of a '"rotation" uf 



ROTATION OF CROPS. 3i3 

four crops, or a four-field (or four-sliift) system. Other sys- 
tems of rotation will be given hereafter. 

553. The leading object of any system of rotation should 
be, to realize the highest profit from our land, and, at the 
same time, to j^^'^serve or increase its fertility. 

A fertile soil may contain a large excess of some of its 
ingredients. It may contain a great deal more lime, or po- 
tassa, or phosphoric acid, than would be exhausted by many 
years of constant cultivation. This surplus fertility can, of 
course, yield no profit to its owner, until it takes part in the 
production of crops ; meanwhile, it must be as unemployed 
capital. The object, then, should be to make it productive 
as soon as possible, but under such management as will still 
retain enough of each element to secure constant fertility. 
Every crop taken from the land will carry away some por- 
tions of the fertilizing matter of the soil, especially those 
kinds which naturally promote its growth. But the same 
crop will take largely of some of these substances, and but 
little, comparatively, of others. The grain crops will remove 
potassa and phosphoric acid abundantly, while they take 
away less of lime and sulphuric acid. The leguminous 
crops, on the other hand, such as peas and clover, carry 
away lime and sulphuric acid much more freely than do the 
grain crops, while they require less of potassa and phospho- 
ric acid than is required by the grains. 

554. Again, while the grain crops exhaust the ammonia 
of the soil very rapidly, they absorb none directly from the 
air; but the leguminous plants are known to collect nitrogen 
(most probably in .the form of ammonia'^') directly from the 
air, and hence require less of this important fertilizer from 
the soil. On the contrary, such crops increase the quantity 

* Some chemists think that these plants absorb ]pure nitrogen, and 
assimilate it ; but this is not fully proved. 



3 f4 ROTATION OF CROPS. 

of ammonia, whenever they are turned down, and allowed 
to decay in the soil. 

We see, then, that one class of plants will rapidly exhaust 
■one set of mineral ingredients, while another class will ex- 
haust a different set with equal rapidity. If one class of these 
crops were cultivated exclusively, it would, by and by, render 
the soil deficient in some of its elements, while others, re- 
quired in less quantities, would still be present in excess. 
But if other kinds of crops were cultivated in rotation with 
these, then all the various elements would be consumed in 
somewhat uniform proportions. We see, too, that while the 
grains are exhausting the ammonia from some of our fields, 
the peas and clover are increasing the supply on others, and 
preparing them to nourish succeeding grain crops. They 
also digest mineral matter, and, as they decay, yield it as 
mineral food for the grain. 

555. The physical, as well as the chemical, condition of 
the soil, may be benefited by proper rotation. In the culti- 
vation of corn and tobacco, the land is kept clean, and 
deeply and frequently stirred, while, in the cultivation of 
wheat, no stirring is done after the crop has been planted. 
Then, in such a system of rotation as gives a crop to be 
turned down very frequently, there is a constant accumula- 
tion of humus, derived from the carbonic acid and moisture 
of the air, and incorporated into the soil, which tends to 
improve the majority of lands. The physical condition must 
be such as to enable the chemical changes, which promote 
fertility of soil and growth of crops, to go on freely; and 
also to bring about the most favorable cennection between 
the plant and the soil. 

556. Hence, any good system of rotation will have refer- 
ence: (1) To the chemical condition of the soil — to the 
proper preseriJafj'bTi, and yet gradual consumption, of its 
mineral dements, and to the restoration of the supply of 



ROTATION OF CROPS. 345 

Immxis and ammonia; and, (2) To keeping the land in the 
best possible physical condition, by the varying culture 
adapted to the diflPerent crops. 

557. Caution. — It must be remembered that while rota- 
tion may enrich a soil, if properly managed, so far as humus 
and ammonia are concerned, it can never increase the quan- 
tity of any mineral element present; but, on the contrary, 
every crop which is carried from the field, must carry some 
mineral fertilizers with it. These cannot be restored by 
plowing down clover and peas. The condition of the mine- 
ral matter already present, may be improved by these crops, 
and thus fitted for future use ; but the quantity cannot be 
increased. Hence, the application of manures must accom- 
pany any system of rotation. 

558. Order or Rotation. — The order in which any 
series of crops, embraced in a system of rotation, must suc- 
ceed one another, may vary with variations of soil ; but they 
should generally follow each other in such succession, that 
the one may leave the soil in good order /or the next which is 
to follow. Tobacco or clover fallow leaves the land in good 
order for wheat, while the cultivation of wheat leaves it in a 
good condition for clover. But clover cannot conveniently 
succeed either corn or tobacco, because neither the season of 
culture, nor the condition in which these crops leave the 
surface, make their tillage a suitable preparation for clover. 

559. The rotation adopted in different sections of country, 
must vary to suit the kind of products chiefly cultivated. Every 
section has one or more leading crops. These are the chief 
sources to which the farmer must look for his profits. In 
some places, corn is almost the sole grain to which attention 
is given; and, together with clover and grass, constitutes the 
whole product of the soil. In other places, tobacco is the 
chief object of attention; in others wheat, or wheat and 
corn with clover. Cotton, in some parts of the South, is the 



o46 ROTATION OF CROPS. 

leading crop, and all others are secondary to it. The system 
of rotation of one region, then, may not suit another having 
a different climate, and producing different crops, any more 
than the same time of planting will suit all places alike. 
Having the general principles here furnished before him, acd 
some examples to be given hereafter, the planter must exer- 
cise his own common sense, aided by experience and close 
observation, in coming to a decision as to what system will 
best suit his climate, soil, and leading products. The crop 
which yields the highest return, in the form of clear profit, 
should be most highly favored in the rotation pursued. 

560. Manuring. — Every farmer should not only have his 
regular system of rotation in cropping, but should also have 
engrafted upon this a system of manuring. In this he 
should look, first, to a speedy and abundant return for his 
capital and labor ; secondly, to the permanent improvement 
of his land. If manures yield the greatest profit when ap- 
plied to corn, let the corn be the chief crop to which they 
are to be applied ; or if they are most profitable on corn to 
be followed by wheat, let them still be applied to the corn. 
Or if they pay better on wheat directly applied, or on wheat 
with the succeeding clover crop, let that point decide the 
question as to how they are to be used ; and so, if they may 
be more profitabl}'' applied to tobacco, or cotton, let them go 
in that direction. 

In some cases, it is best to multiply the quantity of manure 
by employing it first in the cultivation of clover, and then 
plowing down the clover as fallow. This may be advanta- 
geously done for either corn or wheat. The fertility of the 
manure (if applied in Winter or Spring) is taken up by the 
clover, and the quantity greatly increased from the air; 
while the mineral matter of the soil is also becoming incor- 
porated with it. This crop afterwards turned down, gives 
far more fertilizins; matter to the soil than would be afforded 



ROTATION OF C U O T S , 317 

by the manure whicli it has consumed during its growth. 
The shading influence of the clover also tends to hasten the 
decomposition of any surplus portions of manure, left unfer- 
mented upon the suriace of the field. Such manuring must 
then be followed by such a succession of crops as will make 
it " pay best." The systems given below will serve as a 
general guide on this point. 

561. Division of Land. — Before any complete system 
of rotation can be successfully carried out, the farm must be 
divided into fields, or sections of fields, nearly equal. These 
must correspond in number with the number of years em- 
braced in the rotation. Where the same crop is cultivated 
year after year for a long time, on the same soil, as may be 
done successfully in some cases, it is not a rotation at all. 
But we sometimes see two crops grown the same year on the 
same land, the one to be gathered, and the other to be turned 
down for manure. Corn and the Southern Pea may be so 
cultivated, where the summer season is long.* The peas are 
planted at the last working of the corn, and afterwards plowed 
down to enrich the soil for the next corn corp. This is the 
simplest form of rotation ; but, as it embraces only one year, 
it requires only one field. If the two crops required two 
years for their growth, as in the alternate culture of wheat 
and clover, or of tobacco and peas, two divisions of land 
would be necessary. So, if the rotation includes any num- 
ber, as four or five crops, each requiring one season for itself, 
there must be four or five fields. These are called " two- 
field, three-field, four-field rotations," etc., according to the 
number of fields or divisions included. 

The number of crops is not necessarily equal to the num- 
ber of fields. The same crop may appear more than once in 

* Journal Va. State Ag. Society, vol. ii. p. 1C5. 



IS 



ROTATION OF CROPS. 



the series, as seen in Mr. rai0in\s "six-field rotation," given 
below. 

502. A taliular view of several systems of rotation will 
now be given. Tliese may serve as illustrations of what has 
been said, and may be useful as guides to the young farmer 
in arranging his own system. 

The divisions of land, or fields, are indicated by the letters 
(A, B, C, etc.) at the tops of the columns containing the 
names of the crops. The successive years embraced in the 
rotation, in each case, are indicated by the numbers (1st, 2d, 
od, etc.) in the left-hand column. 



TWO-FIELD ROTATION (a). 
Crops. — Wheat and Clover. 
Years. Field A. FieM C. 

Ist Wheat, Clover. 

2J Clover, Wheat. 



TWO-FIELD ROTATION (b). 
Crops. — Cotton and Peas. 
Ye;irs. Field A. Field B. 

1st Cottou, Peas. 

2d Peas, Cotton. 



These are very simjjle systems of rotation. The former 
(a) I have seen practised with success for a number of years 
together. The method of manuring in this case is to apply 
plaster and ashes to the clover, and the organic manures to 
the wheat when sown. The second system (7*) is frequently 
adopted in some cotton-growing sections. Plaster and ashes 
may be applied to the peas — organic manures to the cotton. 



THREE-FIELD ROTATION ((l). 

Crops. — Corn, Wlieat, Clover. 
Years. A. li. C. 

1st Corn, Clovei', Wheat. 

2d Wheat, Corn, Clover. 

od Clover, Wheat, Corn. 



THREE-FIELD ROTATION (J}). 
Crops. — Tobacco, Wheat, Clover. 
Years. A. B. C. 

1st... Tobacco, Clover, Wheat. 
2d ... \Vheat, Tobacco, Clover. 
3d ... Clover, Wheat, Tobacco. 



Each crop in both of these systems, it will be seen, has 
taken the round of all the fields. Manures may be applied 
very successfully as a top-dressing to the clover in Winter 
or .Spring. 



ROTATION OF CROPS. 



349 



FOUR-FIELD ROTATION (rt). 

Crops. — Corn, Outs, Wheat, Clover. 
Years. A. B. C. D. 

1st Com, Clover, Wheat, Oats. 

2d Oats, Corn, Clover, Wheat. 

3d Wheat, Oats, Corn, Clover. 

4th Clover, Wheat, Oats, Corn. 



FOUR-FIELD ROTATION (h). 

3 Crops. — Corn, Wheat, Clover. 

Years. A. B. C. D. 

1st r Corn and) ^.j^^.^^.^ Clover, Wheat. 

(. Tobacco, i 

2d Wheat, f Corn and I clover. Clover. 

I Tobacco, J 

3d Clover, Wheat, / Corn and | qxq^^y^ 

y. Tobacco, J 

4th Clover, Clover, Wheat, f Com and 

l Tobacco. 

In the rotation (a) above, corn is planted on a clover sod. 
The corn leaves the land in fine condition for oats, while the 
latter on many soils is regarded as affording a good prepara- 
tion for wheat. In the second case (i), it will be seen that 
each field lies in clover two years in succession. The clover 
should be cut at least once the first year, to secure a good 
crop the second year (§ 487). Manures, both organic and 
inorganic, should be applied at least once in every circuit of 
the rotation (a). The rotation (h) will improve any soil 
capable of producing clover, provided the fields are not pas- 
tured, if only mineral manures, such as ashes, plaster, and 
bone-dust, are applied. The growth of clover alone will give 
organic matter in large and yearly-increasing quantities. 
Where much pasturing is necessary, a greater number of 
fields must be embraced in the system. 
30 



350 



ROTATION OF CROPS. 



FIVE-FIELD ROTATION OF EASTERN VIRGINIA. 

Ckops. — Corn and Peas, Wheat, Clover, Wheat, Pasture. 



Years. 

1st. 
2d. 
3d. 
4 th. 
5th. 


A. 


U. 


c. 


D. 


E. 


Corn and 
Pea-fallow 

Wheat 

Clover 

Wheat 

Pasture .... 


Pasture.... 

Corn and 
Pea-fallow 

Wheat 

Clover 

Wheat 


Wheat 

Pasture .... 

Corn and 
Pea-fallow 

Whe.at 

Clover 


Clover 

Wheat 

Pasture .... 

Corn and 
Pea-fallow 

Wheat 


AVheat 
Clover 
Wheat 

Pasture 

Corn and 
Pea-fallow 



This system gives one field in corn every year, upon 
which, at the last plowing, peas are sown broadcast, to be 
fallowed for wheat. Two fields are cultivated in wheat every 
year : one in clover, for cutting or fallow, or for both, and 
another in clover or grass, for pasture. As wheat is here 
the leading crop, unfermented manures should be applied to 
the clover to be fallowed ; fermented manures, such as guano, 
to the wheat directly. This rotation is well adapted to a 
wheat-growing region far enough south for the growth of the 
southern pea.* Tobacco may be brought into this system, 
in connection with corn, as preparatory for wheat. 

SIX-FIELD ROTATION (^Mr. Rvffin's). 

Crops. — Corn, Peas [broadcast). Wheat on Pea-falloxv, Clover, Wheat 
on Clover-fallow, Pasture. 



YL';irs. 


A. 


B. 


C. 


D. 


E. 


F. 


1st... 


Corn ... 


Pasture 


Wheat . 


Clover.. 


Wheat . 


Peas 


■Id ... 


Peas ... 


Corn ... 


Pasture 


Wheat . 


Clover.. 


Wheat 


;id ... 


Wlieat . 


Peas ... 


Corn ... 


Pasture 


Wheat . 


Clover 


4th.. 


Clover.. 


Wheat . 


Peas ... 


Corn ... 


Pasture 


Wheat 


5th.. 


Wheat . 


Clover.. 


Wheat . 


Peas ... 


Corn ... 


Pasture 


6th.. 


Pasture 


Wheat . 


Clover.. 


Wheat . 


Peas ... 


Corn 



Journal of Virginia State Agricultural Society, vol. ii., p. 134. 



ROTATION OF CROPS. 351 

This system differs from the five-field system given above, 
in allowing the pea crop the benefit of an entire field, and a 
full season of growth. It has been well tested, and is found 
highly improving to the wheat-growing farms of Eastern 
Virginia. 

Various other systems of rotation are in use in different 
regions of our own and other countries. These have been 
given as specimens, suggestive to the young farmer. 

563. Secondary Rotations. — On every farm there are 
some smaller lots, set apart to be cultivated in such crops as 
could not be brought under the general system of rotation 
adapted to the main body of the farm. Such are the lots 
appropriated to potatoes, cabbage, &c. These, as well as 
the larger fields, should be cultivated according to the prin- 
ciples here laid down. Cabbage, potatoes, wheat, and clover, 
make a good series for a rotation. 

A lot of the richest loamy soil, which can be conveniently 
set apart for this purpose, and of sufficient size to meet the 
wants of the farm, should be surrounded by a close, strong 
fence, proof against pigs, as well as larger animals. It 
should then be divided into four sections. A, B, C, and D, 
about equal to each other. The first year, let A be deeply 
broken up and sub-soiled (drained, if necessary), well dressed 
with manure, stirred thoroughly, and planted in cabbage, 
which is a highly nutritious vegetable, and very much rel- 
ished by laboring men. If B cannot be conveniently brought 
under clover, let peas or some other fertilizing crop be sub- 
stituted, as preparatory to cabbage the second year. Let C 
be sown with wheat, and D be cultivated in potatoes. This 
will introduce the rotation, which may then be kept up as 
represented in the following table: 



552 



QUESTIONS. 



Years. 


A. 


D. 


C. 


D. 


1st... 
2d... 
3d ... 
4th.. 


Cabbage .... 
Potatoes.... 

Wheat 

CloverorPeas 


Clover or Peas 

Cabbage 

Potatoes 

Wheat 


Wheat 

Clover 

Cabbage .... 
Potatoes .... 


Potatoes 
Wheat 
Clover 
Cabbage 





The first crop of clover may be cut oflF every season, and 
either be fed green, or made into hay. The second growth 
should be left on the ground, and turned down in the Autumn 
or Winter. 

564. GrAKDENS. — The same principles which have been 
applied to field rotation are equally applicable to garden cul- 
ture. The plots should here be arranged under a few general 
divisions. Each of these should then be sub-divided, and 
appropriated to plants of the same general character. Those 
that are cultivated on one of these leading divisions ought to 
be transferred to another the next season ; then let plants of 
a somewhat different class succeed them. Thus the garden 
rotation may be kept up by groups, instead of single crops. 
Such root vegetables as beets, parsnips, and salsify, may be 
thrown into one group, and cultivated on contiguous beds; 
the different varieties of beans and peas naturally constitute 
another group; and so, by general similarity, by time of 
planting, or by some other circumstance, a convenient classi- 
fication may be made, upon which a system of rotation can 
be based. 



QUESTIONS ON CHAPTER XXIV. 

§ 552. What is meant by "rotation of crops?" What is said of 
the division of the land? Explain the example given for illustration. 

553. What should be the leading object of any system of rotation? 
How does the rotation of crops make the elements of fertility more 
profitable ? 

654. How does rotation affect the ammonia of the soil ? Whence 



QUESTIONS. 353 

do cfops get their nitrogen? What would be the effect of the long- 
continued cultivation of any one crop? 

555. How may rotation improve the physical condition of the soil? 

55G. To what two points must a system of rotation have special 
reference, as far as regards the soil ? 

557. Can the humus and ammonia of the soil be increased by pro- 
per rotation of crops ? Can the mineral fertilizers be increased in 
the same way ? Why ? 

558. Is the same order of rotation suited to all soils? Why not? 

559. Is the same system of rotation adapted to all sections of the 
country? What is said of leading crops? What must guide the 
farmer in deciding what sj'stem will best suit his purposes ? 

6G0. Is rotation in manuring important? What points require 
special attention? How may the quantity of manure be multiplied? 
How does clover increase the efficiency of manure ? 

561. How should the land be divided before introducing a rotation 
of crops ? Under what circumstances may no division of land be 
necessary ? What determines the number of divisions required in 
any case ? 

562. Of what use are the tabular statements given in this section? 
Explain the "two-field rotation." The " three-field rotation." The 
"four-field rotation." The "five-field rotation." The "six-field 
rotation." 

563. What is said of secondary rotations ? What illustration is 
given ? 

564. How may the principles of rotation be introduced into gar- 
dens? 



30* 



354 VALUE OF CROPS AS FOOD. 



CHAPTER XXV. 

VALUE OF CROPS AS FOOD. 

565. The leading object of the cultivation of tlie grain, 
grass, and root crops, is to provide food for man and beast. 
The value of any one of these products, then, must be deter- 
mined by the extent to which it fulfils the end of its culture. 
This must depend upon its proximate composition (§ 133); 
that is, upon the quantity of nutritive matter which it con- 
tains. It has been stated, in Chapter VI., that the animal 
kingdom rs dependent, either directly or indirectly, upon the 
vegetable kingdom for its subsistence. The proximate con- 
stituents which give value to plants have been described in 
the same chapter. Then, in Chapter VIII., we studied the 
proximate constituents of animal bodies. These latter are 
derived from the vegetable compounds, under the influence 
of vitality controlling the processes of digestion, respiration, 
secretion, &c. 

566. The ingredients of plants which serve valuable pur- 
poses as food, are starch, sugar, gum, j^^'oteine matter, oif, 
woodi/ fihre, water, and salts. 

567. /Starch is the most abundant element in grain crops, 
forming about one-half of the weight of the most common 
cereal grains; but in these the proportion varies to some 
considerable extent. Even in the same species of grain, the 
quantity of starch diff"ers in accordance with the circum- 
stances of climate, soil, and culture. The estimated quanti- 
ties given must, therefore, be regarded as only the mean of 
a great variety of samples, serving merely as an approximation 
to the true proportion in any particular case. Wheat con- 



VALUE or CROPS AS FOOD. 355 

tains from 40 to 50 per cent of starch, according to tlie 
variety, influence of climate, &c. Corn varies less widely in 
its proportion of starch, ranging from 40 to 45 per cent. The 
white, soft varieties of both wheat and corn abound most in 
starch. Rye, oats, buckwheat, and beans, do not vary widely 
from corn, nor from one another, in their percentum of this 
element. Rice surpasses all the ordinary grains in the quan^ 
tity of starch it contains, having about 70 per cent. Potatoes, 
in the condition in which they are taken from the ground, 
have about 15 per cent, of pure starch ; and even hay contains 
from 3 to 5 per cent. 

5G8. Gum and Sugar are very similar to each other, and 
very similar to starch, in their nutritive value, as we shall 
learn presently (§ 576). They are found in nearly all of our 
cultivated crops, in quantities varying from 2 to 15 per cent. 
Hay, cut in good time, has more of these substances than 
we find in any of the ordinary grains, except rye. 

569. Proteine comjjounds have been described (§ 154) as 
composed in part of nitrogen. They resemble most of the 
muscular and membranous organs of animals, and constitute 
the elements of food which nourish these parts of the animal 
body. As the greater part of the solid portion of the ani- 
mal is made up of proteine matter, it may be regarded as 
consisting of the concentrated j^roteine of the food consumed 
during its growth. Hence we see the importance of this 
kind of food, in building up the animal system. 

570. Beans and peas contain more proteine matter than 
is found in any other of our common crops. It exists here 
in a form called " legumen" (§ 157), and in quantity as high 
as 25 per cent. The cereals have from 10 to 20 per eeht of 
this kind of matter, chiefly in the form of gluten (§155). 
It is most abundant on the inner surface of the bran, and 
is taken out largely with it, in the preparation of flour. 
This gives to wheat bran a nutritive value greater than its 



356 VALUE OF CROrS AS FOOD. 

appearance would indicate. This important kind of matter 
is also found in grass, hay, and to some extent in straw. 
Green clover, and clover hay, also hay made of pea-vines, 
owe much of their value to the presence of proteine matter. 
Cabbage contains not a little of it, and is hence quite nutri- 
tious. Of all the grain crops in ordinary use, none contain 
so little of this important element as rice. 

571. Oil is found to exist in some form in almost every 
plant, and in almost all parts of every plant. In passing 
through the digestive organs, the vegetable oils undergo such 
modifications as convert them into the varieties of fat pecu- 
liar to diiferent animals. Those grains which abound most 
in oily matter, within certain limits, are best fitted for food, 
where fattenimj is the leading object. Some seeds, such as 
those of flax, hemp, and cotton, contain too much oil to be 
fed alone. These seeds are ground into meal, and have their 
oil pressed out by machinery, for use in the arts. The cakes 
which are left, still contain enough of oil, together with their 
starch, gluten, etc. to make them valuable as articles of food 
for stock. Indian corn has a larger quantity of oil in it, 
than is found in any other of the cereal grains, having from 
8 to 10 per cent. Oats, which have about 5 or 6 per cent, 
come next in order. Wheat and rye contain 2 or 3 per cent 
of oil, while rice and buckwheat have not more than 1. The 
oily matter in good hay ranges from 2 to 4 per cent, and it 
is by no means wanting in straw which has been cut in good 
time. 

572. Woody fibre, when dried, is chiefly indigestible, and 
yet it serves an important purpose in promoting the digestion 
of other constituents of food, with which it is mingled. Its 
presence makes the mass of food porous, so as to be easily 
penetrated by the fluids of the digestive organs. It also 
keeps the stomach and intestines properly distended (§631, b'). 
Hay and straw are composed to a great extent of woody 
fibre. In the grain crops, the bran contains most of the fibre. 



VALUE OF CROPS AS FOOD. 



357 



573. Water is a constituent of the dryest articles of food. 
The ripest grain, and the dryest straw and hay, have seldom 
less than from 8 to 12 per cent of water in them, under ordi- 
nary circumstances. Potatoes contain about 75 per cent of 
water, while turnips, and other root crops of a similar kind, 
have as much as 85, and sometimes even more. 

574. The mineral elements contained in food crops, are not 
to be disregarded in estimating their value. The animal sys- 
tem demands mineral as well as organic elements, to promote 
its growth and healthy development. The bones must be 
provided with phosphate of lime, and the fluids of the body 
with salts of soda and potassa. These, with other mineral 
substances found in the animal body, must have their origin 
in the food consumed. By referring back to Table III, it 
will be seen that the ashes of the grain crops contain most 
largely the phosphates and alkaline salts, — just the minerals 
chiefly demanded by the animal. 

575. The following Table gives about the average compo- 
sition of the crops most extensively used as articles of ani- 
mal food; but as they vary in composition under changes of 
climate, and from other causes, the numbers here given must 
be regarded as giving only the general average in each case. 



TABLE VIII. — VEGETABLE FOOD. 



In 100 lbs. 


Si 

48 
9 

17 
2 

10 

12 

2 
100 


n 
Q 

45 
8 

IS 
9 
9 

12 

2 
100 


>> 

K 

41 
14 
13 
3 

15 
12 

2 
100 


"a 
O 

30 

5 
11 

5 
33* 
13 

3 

100 


■*-j 

03 

.a 

3 

n 

45 

5 
10 

1 

26* 
11 

2 

100 


S, 

40 
6 

25 
3 

10 

14 

3 
100 


i 

4 
6 
1 
4 
12 

1 
100 


d 


1 
O 


o >-. 

3 
12 
7 
3 
50 
15 

9 
100 


o 

5 

3 
IS 
9 
4 
45 
16 

10 
10.) 


is 

1 

7 

2 

2 

70 

12 

6 
100 


i 

4 
10 
12 

2 
52 
15 

100 


Starch 

Gum and Sugar. 
Proteine Matter. 

Oily Matter 

Vei^etablo Fibre.. 

Water 

Minerals in I 
Ashes J ■■ 


15 

.*< 

74 
1 

100 


2 
3 
3 

2^ 

88 

1>^ 




100 



* The chaffy husk of oats, and the, black husk of buckwheat, are both composed 
chiefly of fibre. 



358 VALUE OF c 11 r s as food. 

In the foregoing Table, equal quantities (by weight) of 
the sevei'al crops are compared, and we are thus enabled to 
estimate the quantity of each of the proximate elements 
consumed with a given weight (say 100 lbs.) of each kind 
of food. If, for example, a horse consumes 100 lbs. of corn, 
he consumes of starch 45 lbs. ; of gum and sugar, 8 ; of 
proteine mattei*, 18 ; of oil, 9. But in 100 lbs. of clover 
hay he eats only about 3 of starch ; of gum and sugar, 13 ; 
of proteine matter, 9; of oil, 4. If 100 lbs. of potatoes 
were consumed, the corresponding quantity of starch would 
be five times as great as in the hay, but the quantity of other 
nutritive substances would be greatly less. The water, which 
constitutes the greater part of the weight of potatoes, has no 
money value, because it is easily obtained from other sources. 
So, we place a low estimate upon woody fibre, because of its 
abundance, though it is important in forage. 

576. Of the substances which give to articles of food their 
chief value, we place the proteine compounds first ; because 
they do most towards building up the animal system — they 
are most nutritious. In fact, they are often spoken of as 
constituting the nufritious part of food. They are certainly 
more largely appropriated in the nourishment and growth of 
animals, than are any other forms of food ; but the oily por- 
tions, which may be regarded as next in importance in feed- 
ing, certainly deserve to be regarded as nutritious; for on 
these, to a great extent, the fattening of animals is depend- 
ent. Starch, gum, and siigar may be classed together, since 
they serve a like purpose in sustaining animal life. After 
undergoing digestion, they are all thrown into the veins, 
where they become a constituent part of the blood, to be 
consumed during respiration (§ 611). These are sometimes 
called "respiratory food," because tl icy are chiefly consumed 
by the oxygen conveyed to the blood in breathing. 'Jliey 
are not less essential to animal life than other forms of diet; 



VALUE OF CROPS AS FOOD. .o59 

yet, from their abundance in vegetable products, tliey are not 
estimated at so high a value as the proteine and oily parts 
of plants. 

577. To estimate the value of the crop grown upon a given 
piece of ground, we must not simply take into account the 
relative quantities of these three kinds of food (the nutri- 
tive, the fattening, and the respiratory) contained in a given 
weight of the crop, but the quantities contained in the whole 
product of the land. A hundred pounds of potatoes contain 
only about one-eighth as much proteine matter as the same 
weight of corn, one-ninth as much oily substance, and one- 
third as much starch. This shows that a given weight of 
potatoes is far inferior in A^alue to the same weight of corn. 
But when we come to compare the products of an acre of 
land cultivated in corn, with the products of an acre culti- 
vated in potatoes, the case stands very differently. In order 
to institute such a comparison, we may suppose that an acre 
which would yield 60 bushels, or about 3500 lbs. of corn, 
would, if properly cultivated, yield 400 bushels, or 20,000 
lbs. of potatoes. Now, 3500 lbs. of corn contain, according 
to the preceding table (Table VIII), 630 lbs. of proteine, 
815 lbs. of oil, and 1855 lbs. of starch, sugar, and gum; 
while 20,000 lbs. of potatoes contain 400 lbs. of proteine 
substance, 100 lbs. of oil, and 3300 lbs. of starch, sugar, 
and gum. If, then, we estimate the feeding value of these 
crops by the quantities of their proteine and oily substances 
alone, the corn has greatly the advantage, but if we bring 
the starch, etc. into the account, the potatoes again surpass 
the corn. 

578. Let us now assume some relative value per pound, 
which may be attached to each of these three kinds of food. 
Suppose the starch, etc. in corn or potatoes to be worth one 
cent per pound for feeding stock, while the proteine and oily 
substances are worth three cents per pound. Then the acre 



3G0 



VALUE OF CROPS AS FOOD. 



of eora will give starch, sugar, and gum, worth $18.56; 
pruteiuc and oily matter, worth $28.35 ; total, 34G.90, ex- 
clusive of the value of the fodder. The acre of potatoes 
will give starch, etc., worth $33.00 ; proteine and oily mat- 
ter, worth $15.00 ; total, $48.00. Under the suppositions 
here made, the products are nearly equal ; but the labor re- 
quired by the potato crop is greater than that required by 
the corn, and for this due allowance must be made. 

579. In order to compare at a glance the forage value of 
the prohaUc products of an acre of several common crops, 
with, reference to the three classes of food we have been 
considering, let us arrange them in tabular form. In the 
first column we place the probable average products in bushels 
and pounds; in the second, third, and fourth, the quantities 
of the three classes of food in each crop; and, lastly, the 
money value under the suppositions just made. Wlieat is 
not included, because it is especially appropriated to man, 
and hence has a higher value than could be assigned it as 
forage. This Table must not be regarded as giving accu- 
rate estimates, but simply as indicating the proper method 
of comparing crops, so as to determine their relative value 
in feeding. 



TABLE IX. 



FORAGE VALUE OF SOME CROPS. 



One Acre, producing 


Starch, 
Sujiar, 
& Gum. 


Prote'c! 
Mat- 
ter. 


Oil. 


Money 
value (?). 


Corn, 30 bus. =r 1,750 lbs. 


927 


315 


158 


$23.46 


Oats, 40 " = 1,300 " 


455 


143 


G5 


10.79 


Peas, 20 " = 1,200 " 


540 


300 


36 


15.48 


Potatoes, 200 " =10,000 " 


ICoO 


200 


50 


24.00 


Cabbage, 10 tons. = 20,000 " 


1000 


GOO 


100 


31.00 


Clover Hay, U " = 3,000 " 


480 


270 


120 


16.50 


Pea Hay, IJ " = 3,000 " 


420 


360 


60 


16.80 



If the ])eas and the pea hay above given are both the 
product of the same acre of ground, as may be the case, the 



QUKSTIONS. 361 

sum of their values is $32.28. When the fodder of corn 
and the straw of oats are preserved, these must be added to 
the grain crops. 

In order to understand clearly the relation of the animal 
kingdom to the vegetable, and to comprehend the principles 
which should regulate the application of crops to feeding, 
and which should guide us in the general management of 
animals, we must direct our attention for a little while to 
some of the leading points of " Animal Physiology." 



QUESTIONS ON CHAPTER XXV. 

§ 565. What is the leading object of the cultivation of the soil? 
How is the value of a crop determined ? What is meant by the 
"proximate composition of plants" (133)? Whence do animals 
generally get nourishment? 

5G6. What ingredients of plants are valuable for food ? 

567. Which is the most abundant proximate element in the grain 
crops? Of what is starch composed? Is the proportion of starch 
constant in the same grain? What per cent, is found in wheat? In 
corn, rye, oats, &c. ? In rice? In potatoes? In hay? 

508. To what are gum and sugar similar in composition? Are 
they abundant? 

569. What are proteine compounds (154).? Why are they import- 
ant in the nutrition of animals? 

570. What is here said of beans and peas? What is "legumen" 
(157)? How much of it in beans and peas? AVhat is "gluten" 
(155)? Where found? Why is cabbage nutritious? 

571. Is oil widely diffused? How does it become valuable in 
feeding ? Do any gi-ains contain too much oil to be fed alone ? What 
per cent, of oil in the several grains? 

572. Is woody fibre digestible ? Why then has it any value ? 
What crops are composed largely of this substance? 

573. What is said of water in articles of food, and of its value? 

574. Why are the mineral constituents of food not to be disre- 
garded ? What do you learn on this subject from Table III. ? 

575. What is given in Table VIII. ? How are the several crops 
here compared? If equal Avcights of different articles have been 

31 



362 QUESTIONS. 

given to an animal, do they always afford equal amounts of nutritious 
matter ? How is this illustrated ? 

576. What compounds stand first, in estimating the value of arti- 
cles of food? Why are these placed first? AVhat stands next in 
value? Why? Why are starch, gum, and sugar, classed together? 
What part do they perform? Why are they not as highly valued as 
profeine and oily compounds? 

577. How can we fairly estimate the value of the products of a 
given quantity of land? What examples are given? 

578. How may the value in money of different crops be deter- 
mined ? Illustrate. 

579. What is the object of Table IX. ? Why is wheat not included ? 
For Tvhat reason should we now give some attention to "Animal 
Physiology " 



ANIMAL niYSIOLOGY. 363 



CHAPTER XXVI. 

ANIMAL PHYSIOLOGY. 

580. Animal Physiology treats of the functions per- 
formed by the various organs of animals. But in order to 
get a clear view of the offices fulfilled by these organs, we 
must examine their structure to some extent. Wc here 
have a very wide field, of which we can look only into a very 
limited portion. As every man should have some knowledge 
of the structure and functions of the organs of his own body, 
that he may know how to preserve them and promote their 
healthful action, so the farmer should have not only this 
knowledge with regard to himself and the members of his 
household, but also with regard to the different kinds of ani- 
mals which stock his farm. 

There is a close analogy between the organs of man and 
those of the lower animals. We shall frequently refer to 
this resemblance, and shall make use of the organs of man's 
body as ti/jjcs of the most perfect structure. 

581. The Skin. — All the animals of which we shall speak 
have their bodies enveloped in a tough, elastic, external 
covering, which consists of two distinct layers. That which 
forms the outer surface is called the " cuticle ;" * and that 
which lies next to the flesh is called the " true skin " (cutis 
vera). 

582. The cuticle is generally very thin, and almost trans- 
parent. It has no blood-vessels or nerves, and may be 
removed from the surface without pain. On the palms of 

* Also called "Epidermis." 



3G4 ANIMAL PHYSIOLOGY. 

the hands and soles of the feet it is made thick and strong, 
so as to protect these parts of the body, which are exposed to 
most constant friction and pressure. With a sharp knife or 
razor, thin shavings of cuticle may be cut from the front 
part of the hand, without exposing either nerves or veins. 
But if the whole thickness of the cuticle is removed, so as 
to expose the outer surface of the cutis vera, a smarting pain 
is felt, from the contact of the air with the nerves which are 
then laid bare. (See Fig. 49.) 

The cuticle has various openings in it called <' pores," 
through which the perspiration from the true skin passes out 
to the surftice. There are other openings also, through 
which oily secretions are thrown off. The number of pores 
in the cuticle is immensely great. Wilson says, " 2800 might 
be taken as a fair average of the number of pores in the 
square inch" of the human body. 

The lower surface of the cuticle consists of a colored layer. 
The coloring matter is secreted under the influence of the 
light and heat of the sun. In this respect there is an 
analogy between the animal and vegetable kingdom. It has 
been shown (§ 179,) that the leaves of plants require the 
light of the sun to develop their coloring principle ; so we 
find the human skin varying in color, in the same individual, 
very much in proportion to its exposure to the sun-light. 
The activity of the skin's secretions is promoted by light. 
If the light is too much excluded, the health of the animal 
body, like that of the plant, is impaired. The dark races of 
men doubtless derive their peculiarities of color, {71 part, 
from long-continued exposure to the sun, for generation 
after generation, until color, like other peculiarities, becomes 
hereditary. 

The cuticle is continually (jruicing, and, as new layers are 
formed beneath, the outer surface becomes dry and scaly, 
and gradually disappears. Where the skin is naked, the 



ANIMAL PHYSIOLOGY. 3G5 

scaly portions are I'emoved by ordinary friction as fast as 
they are formed ; but where the svirfuce is covered with hair, 
they accumulate and form scurf. The healthy action of the 
skin of all animals is promoted by the frequent removal of 
this accumulation. Washing with soap softens and removes 
the surplus dead cuticle from the pkin, and with it particles 
of dirt which have become imbedded in it. 

583. The ntlis vera (true skin) is composed of two layers; 
the outer one consisting of very minute bundles of fibres, so 
closely interwoven as to give it quite a compact structure. 
It is pervaded by a great number of veins and arteries which 
circulate the blood through it, and convey the necessary 
nourishment both for it and the cuticle. These veins and 
arteries arc also accompanied by nerves, which make this 
layer of the skin very sensitive. Where the veins and arte- 
ries meet, they form little projections or elevations, called 
** papilla)," which make the surface of the skin uneven. 
The papilla) may be distinctly seen as little, red, conical ele- 
vations on the surface of the tongue. This layer is called 
the "sensitive, or papillary tissue" (Fig. 49). The inner 
layer of the true skin is much thicker, and more coarsely 
fibrous in its structure. Its veins, arteries, and nerves, are 
numerous, but fewer in number, though larger, than those 
of the sensitive layer. In this, the oil-glands of the skin 
are imbedded, and ai'e connected with the surface by tubes 
passing up through the cuticle. These oil tubes usually 
open in pairs into the sheaths of the hair, and thus provide 
the natural oil which gives the hair its beautiful glossy 
appearance. The persjyiratory glands are also situated in 
this part of the cutis vera. They separate impurities from 
the blood, and throw them out with the perspiration through 
the cuticle at the pores. 

584. There are cells in the lower part of the true skin 
filled with fat. Such cells form what is called " adipose tis- 

31* 



366 



ANIMAL P H Y S I L O O Y. 



sue." The following figure, from Cutter's Anatomy and 

Physiology, will aid the student in getting a clear idea of 

ihn •• ■'itive situation of the parts of the skin, as described 

It represents a vertical section of the skin, through 

thickness, but greatly magnified. 



Fig. 49. 




Fig. 49. — 1, 1, The lines, or ridges of the cuticle, cut perpendicularly. 2, 2, 2, 2, 2, 
The furrows, or wrinkles of the same. 3, The cuticle. 4, 4, 4, The colored layer of 
the cuticle. 5, 5, The cutis vera. 6, 6, 6, 6, 6, The papillae. 7, 7, Small furrows 
between the papillae. 8, 8, 8, 8, The deeper furrows between each couple of the 
papilla?. 9, 9, Cells filled with fat. 10, 10, 10, The adipose layer, with numerous 
fat vesicles. 11, 11, 11, Cellular fibres of the adipose tissue. 12, Two hairs. 13, A 
perspiratory gland, with its spiral duct. 14, Another perspiratory gland, with a 
duct less spiral. 15, 15, Oil-glands with ducts opening into the sheath of the 
hair (12). 

585. Functions of the Skin. — The leading ofiice of the 
skin 4s to protect the surface of the body. For this purpose, 
it is most admii'ably adapted by our beneficent Creator, being 
made both tough and elastic — resisting all ordinary forces in 
the form of blows and friction, yet yielding to slight pres- 
sure, and to the bending of every joint. The cuticle is made 



ANIMAL P II y S I O L O G y. 3G7 

without nerves, that it may cover the more sensitive layer 
beneath ; and yet it lies so closely in contact with the web- 
work of nerves on which it rests, that almost the slightest 
touch, even a breath of air, makes known its presence 
through these little nervous channels j the sensation, how- 
ever, is made pleasant by the intervening of the cuticle, 
while it would be extremely painful if this layer were re- 
moved. When injured or broken, the cuticle is renewed 
very rapidly, while the bruised surface beneath throws out, 
in the mean time, liquid matter which, drying, leaves a scab 
over the surface as a temporary protection. 

The cuticle is constantly worn away by friction, but it as 
constantly grows again ; and when the amount of friction or 
pressure becomes greater than usual, and is rapidly applied, 
it is sometimes worn off, so as to expose the sensitive layer 
below, and sometimes only loosened from its contact with this 
layer, causing the secretion of fluid matter beneath, giving 
rise to blisters. Such effects are seen upon the hands of one 
who undertakes more severe manual labor than he has been 
accustomed to perform, and upon the shoulders of young 
horses when first put into harness. But if care is taken to 
apply the increased pressure and friction gradually, no great 
inconvenience is felt, because the cuticle has the property of 
increasing in thickness, whenever the protection of the other 
layers requires it; provided time enough is allowed for the 
necessary change to take place. 

586. The sensitive layer, by its abundant supply of nerves, 
acts an important part in giving warning whenever an ex- 
ternal body comes in contact with any part of the system. 
If the mind were not thus made conscious of the presence 
and action of outward forces, the body might be seriously 
injured, before the necessary means could be adopted for its 
protection. 

587. T\\Q pores serve as outlets for the perspiration, which 



8G8 ANIMAL r II Y S I L O G Y. 

is constantly secreted from the blood, and carries out in solu- 
tion, surplus matter, both mineral and organic. This process 
is constantly going on. If the temperature of the body is 
much increased by exercise or warm clothing, the perspira- 
tion collects more rapidly than it is evaporated, and forms 
drops upon the surface if naked, or moistens the hair or other 
covering of the skin. At ordinary temperatures, the perspi- 
ration is not thrown out more rapidly than it is evaporated 
from the surface ; but still it goes on. It is then called 
" insensible perspiration." 

Experiment.' — Insert your hand into a dry, clean jar of 
clear glass, having wrapped your handkerchief, or something 
of the kind, around your wrist, so as to close the mouth of 
the jar. In a short time, the inner surface of the glass will 
be covered with a film of moisture. This is the insensible 
perspiration made sensible, by being collected as fast as it 
escapes from the pores of the skin. 

Perspiration is necessary to health in both man and beast, 
hence anything tending to check it, is apt to result in injury. 
The impurities, instead of being thrown out, are retained by 
the blood, and inflammatory diseases are the consequence. 
Sudden chilling of the body, after free exercise, is always 
dangerous. Any one who remains at rest in the cold air, 
after taking violent exercise, should at once increase his 
quantity of clothing. The practice of leaving a horse ex- 
posed to a cold wind after brisk exercise, is very pernicious; 
but to ride him into a deep pond to cool him oft', while he is 
sweating freely, is still worse. The pores of the skin are 
suddenly closed, and inflammation, and frequently conges- 
tion in some part of the body, is a very common result. 

The safest plan for both man and horse, is to rub the skin 
briskly as it cools oft", protecting it at the same time from 
cool currents of air. Or if this cannot be conveniently done, 



ANIMAL PHYSIOLOGY. 3G9 

the man sliould throw a cloak over "himself, and a blanket 
over his horse. 

588. The oily secretions from the skin protect it against 
sudden changes, to some extent, by forming a non-conduct- 
ing film over the surface. They also diminish friction be- 
tween the cuticle, and the bodies with which it comes in 
contact, and thus prevent it from being abraded so often as 
it would be, if the surface were more dry and harsh. 

Cleanliness promotes the healthy action of the skin. 
Children and servants should be required to bathe fre- 
quently, and rub briskly afterwards. A foul skin and foul 
clothing are fruitful sources of disease. Horses, cows, and 
even hogs, should have clean, dry beds ; otherwise, they will 
be liable to cutaneous diseases. 

589. The peculiar structure of the skins of animals, gives 
them their value in the manufacture of leather. The cuticle 
forms the grain of the leather, while the true skin forms the 
main body, and the stronger part of the material. Its pecu- 
liar net-work of fibres gives it both toughness and elasticity. 
For the chemistry of tanning leather, see § 196. 

590. Appendages of the Skin. — Hairs, feathers, nails, 
claws, hoofs, and horns, may be regarded as appendages to 
the skin (§ 201). 

Hairs have their origin in the true skin, and spring from 
a bulb-like root (Fig. 49). They have neither veins nor 
nerves, and hence have no vitality in themselves. They 
grow at the root only ; and the upper part is thrust out by 
the increase of length at the lower extremity. A hair con- 
sists of three parts: 1. The cuticle, or external scaly cover- 
ing; 2. A horny, cylindrical tube, having a fibrous struc- 
ture; 3. A ^5?'</i of cellular structure, forming the central 
axis of hair. These parts may be seen very distinctly in the 
tubular part of an ordinary feather. The tough external 
covering (the cuticle) may be scraped ofi" with a knife — the 



370 



ANIMAL P II Y S I L Y. 



horny part is tlien laid bare ; then within this is the pith, or 
ineihiUa, full of colls which are visible to the naked eye. 

The cells in the centre of a hair are generally filled with 
air, but they readily absorb water, and various kinds of lic^uid 
solutions. The whole hair may be impregnated with water, 
or with a colored solution. The dyeing of wool consists in 
thus conveying coloring substances into the cells of the fibres 
of wool, where it fixes itself, or is fixed by the action of some 
other substance. Sometimes the color is developed by clie- 
mical changes produced within the fibre, by first dipping the 
material to be colored into one solution; then transferring it 
to another, which will form some colored compound with the 
first. 

The surface of hair is not smooth, as might be supposed 
from simply viewing it with the unaided eye. The micro- 
scope shows that the outer coating is made up of numerous 
scales, which generally overlap one another. In the case of 
wool and fur, these are especially 
remarkable. Fig. 50 shows fibres 
of fine wool, as they appear when 
magnified by the microscope. The 
little scaly rings adhere to each 
other, and the fibres, as they are 
worked together in the process of 
felting, or in carding, spinning, 
weaving, etc. form a cohesive, yet 
porous mass. If the surfaces were 
destitute of these scaly projections, 
the fibres of wool and fur would 
be fixr less valuable for the purposes to which they are 
applied. 

591. The nails of man, and the cktu-!^ and hoofs of other 
animals, may be regarded as portions of the cuticle, contrived 
by an all-wise Providence for the defence of those parts of 



Fig. 50. 




ORGANS OF MOTION. o7l 

the hands and feet most exposed to injury. They are en- 
dowed with the property of perpetual growth; so that, as 
the extremities are worn away by use, new portions are 
thrust forward to take the place of what is removed. 

ORGANS OF MOTION. 

592. Bones. — The bones have no power of producing 
motion, but they form the framework of the body. They 
give it strength, and determine the general outline of its 
figure. They are, moreover, the instruments of motion, 
through which the muscles carry on their operations. 

The composition of the bone has been given (§ 204), as 
consisting of a solid mineral portion, chiefly phosphate of 
lime, and a softer organic portion, composed of gelatinous 
matter. The bones are surrounded by a strong fibrous 
membrane, called the " periosteum." To this the tendons 
and ligaments are attached, and thus the bones are connected 
with the muscles and with each other. The periosteum 
covers all parts of the bones, except the extremities, where 
two bones come together to form a joint, and the crowns of 
the teeth, which are coated by a hard bony substance called 
"enamel." This covering of the bones is provided with 
arteries and veins, and through it the bones get their nou- 
rishment. It is also supplied with minute nerves, but is not 
very sensitive, unless inflamed by disease. 

593. The outer portion of the bony substance is usually 
very compact and hard, and forms a strong wall, vai-ying in 
thickness in different bones, and in different parts of the 
same bone. In the slender part, called the " shaft," it is 
thicker than at the projections near the joints. The inner 
part of the bone is porous, and comparatively soft. The 
middle part of the longer ones is tubular, and filled with a 
peculiar oily substance called " marrow." 

594. Wherever two bones meet to form a joint, the ends 



372 



ORGANS OF MOTION. 



of both arc covered with a very strong, elastic cushion, 
called ''cartilage," or "gristle," which yields to any sudden 
pressure, and again expands to its ordinary form. This pre- 
vents the hard parts of the bones from coming in contact, 
and thus preserves the joints from injury. The surfaces of 
the cartilage are extremely smooth, and move upon each 
other with but little friction. The friction is also still fur- 
ther diminished by a liquid secreted around the joint, and 
most perfectly adapted to the purpose for which it is in- 
tended. 

Fig. 51, 



Fig. 52. 





Fig. 51 is a section of a man's thigh-bone (femur) — a, a, a, 
the compact wall within the periosteum ; h, h, the cellular or 
porous part within; c, the marrow. This structure gives 
the bone a remarkable combination of lightness and strength. 



ORGANS OF iM O T I O N. 373 

Fig. 52 represents a joint, with the rounded extremity of 
one bone fitting the hollow extremity of the other, and each 
part coated at the end with cartilage, a, a. 

595. The joints are held together by strong ligaments 
{b, Fig. 52), attached to the convex part of the one bone, 
and the concave part of the other. There is also a mem- 
brane which covers the joint externally, and over this, liga- 
ments of a strong fibrous structure extend from bone to 
bone. 

Some bones are connected by cartilage alone, without 
joints, as seen where the ribs are attached to the breast- 
bone. In such cases, considerable elasticity, with only a 
limited motion, is required, as in the expansion and contrac- 
tion of the chest in breathing. 

596. Functions of the Bones. — These are, Jirst, to 
give the requisite stiff'ness and strength to the various parts 
of the animal; sccondh/, by means of joints, cartilages, etc. 
to give facility and freedom of motion ; tlilrclly, to protect 
other organs, as in the case of the brain, which has around 
it a strong and elastic wall, composed of the several bones 
of the skull ; or the eye, which has its socket within a bony 
cavity; or the organs within the chest, surrounded by a 
most graceful framework, which yields readily to the action 
of these organs, and yet serves as a strong defence against 
external injuries. 

597. In domestic animals generally, slender hones are de- 
sirable, provided the size in other respects is not too small; 
for, if we desire a combination of strength and activity, as 
in a well-formed horse, we shall not find it in large bones. 
The strength of a bone is by no means proportional to its 
size. In an animal of slender, graceful limbs, the bones are 
more compactly formed, and are found to be often stronger 
than those of another, of the same size in body, but having 
thicker and more unwieldy limbs. Again, if we value the 

32 



874 M u S C L E s . 

animal for food, tlie bones must be subtracted. Every one 
must have observed the wide difference in the quantity of 
bone found in different beeves of the same size. Those 
having slender legs and -well-rounded muscles, have small 
bones throughout. The same is true of hogs and sheep. 

MUSCLES. 

598. Surrounding the bones, and attached to them on all 
sides, are the muscles. They consist of bundles of fibres, 
varying widely in form and size, encased in sheaths, or 
coverings of membrane. They constitute the lean flesh of 
the body, give it symmetry of form, and are the true organs 
of motion. The muscles are attached to the periosteum of 
the bones by tendons, or cord-like extremities. The union 
between these and the surface of the bone is very strong. 

Under the stimulating influence of the nerves, the muscles 
have the power of contracting, in such a way as to diminish 
their length, and of again relaxing when the stimulus ceases 
to operate. The loill, acting through the medium of the 
nerves, can stimulate any particular set of muscles, and 
cause alternate contraction and relaxation. 

599. Functions. — The most important office of the mus- 
cles is to produce motion. This is done by their contractile 
force. By contraction they draw after them the bones to 
which they are attached. In bending the elbow, or in clos- 
ing the hand, it will be seen that the middle part or " swell" 
of the muscle is enlarged. This is done at the expense of 
its length; and the extremities being thus brought more 
nearly together, motion of the bones to which they are 
attached must follow. By grasping the arm above the 
elbow with the opposite hand, and then bending the elbow, 
a very considerable enlargement of the muscles in the 
upper part of the . arm will be perceived. These are the 
muscles employed in moving the lower part of the arm. In 



MUSCLES. 



375 



closing; one hand, while the arm between the elbow and wrist 
is held in the grasp of the other, a similar enlargement will 
be felt there. The accompanying -p^^ 53^ 

figure (Fig. 53) shows how the mus- 
cles are attached to the bones, above 
and below the elbow. By contract- 
ing the muscle a, the elbow is bent ; 
and by relaxing this, and at the same 
time contracting h, the arm is again 
straightened. The muscles are thus 
arranged in pairs. Every muscle 
which is employed to bend a joint, 
has its antagonist on the opposite side 
employed again to straighten it. There 
is thus a pair of muscles for every 
motion, and for every variety of mo- 
tion, performed by every organ of the 
body. 

The stimulating influence of the 
nerves upon the muscles cannot con- 
tinue indefinitely. The duration is about inversely propor- 
tioned to the force exerted. Violent muscular effort can be 
of only short duration, while moderate exertion may continue 
much longer without weariness. But the power of endu- 
rance in the muscles may be greatly increased by Jiahit. 
When a man first begins to perform some severe labor, to 
which he has not been accustomed for some time, he finds 
his power of endurance much less on the first day, than it is 
after several days spent at the same work. 

600. The muscles may be permanently injured by too 
violent use, or by too long-continued action without rest. 
Hence we find both men and horses often weakened, or stif- 
fened for life, by too severe, or too long-continued use of 
particular muscles. 




876 ADIPOSE TISSUE. 

If different sets of muscles are brought into action alter- 
nately, they partially relieve one another. A change of po- 
sition gives relief, when we become weary of any posture in 
which we have continued for some time. Sitting affords 
relief to one who has been long standing, while standing 
equally relieves one who has been long sitting. The change 
of position brings a fresh set of muscles into play. So an 
animal, wearied with ascending a hill, is relieved by descend- 
ing. So long as a horse is driven upon a level road, the same 
muscles are perpetually at work ; but when he comes to a 
gentle ascent or descent, it affords him relief. Hence horses 
can make long journeys over a gently undulating country, 
with more ease than over a level plain. 

601. The muscles of young animals are much less com- 
pact and strong than those of animals fully matured. They 
are consequently more easily injured. Boys and young 
horses often have both their strength and activity seriously 
impaired, by being over-worked. Muscular strength is in- 
creased by exercise within certain limits ; but in young ani- 
mals there is danger of exceeding these limits when they are 
subjected to severe labor, as in plowing with young horses or 
oxen. By moderate use the blood is made to circulate freely 
through the muscles, and thus supply increased nutriment, 
which adds to their compactness and strength. 

ADIPOSE TISSUE. 

602. The adipose tissue has the form of little cells or 
sacks. These are filled to a greater or less extent with fat. 
They are most abundant immediately beneath the skin, 
around the kidneys, and in other places where fat is found 
to be accumulated. The cells of this tissue, in a healthy 
animal, are rapidly filled up when the animal is abundantly 
fed on substances well supplied with fattening food (§ 571). 
But if the supply of this kind of food is withheld, they are 



ADirOSE TISSUE. 377 

just as rapidly exhausted of wliat is already accumulated. 
The fat is exhausted to supply the blood with the proper 
elements to keep up the process of breathing (§ G31). Du- 
ring sickness, v/hen the digestive organs are diseased, and 
the proper supply of food cannot be conveyed to the blood 
through the stomach, the fat is withdrawn from the adipose 
tissue, and the whole system becomes emaciated. 

This tissue, when filled, serves as a species of wad- 
ding to the muscles, giving them symmetry of form. In 
young persons there is an abundant supply of fat on the 
lower surface of the skin, giving every part of the body a 
smooth, rounded appearance ; but in old age this supply is 
greatly diminished, and the skin becomes wrinkled. Cor- 
pulent persons have an unnatural accumulation of this tissue 
in almost all parts of the body. 

G03. Animals in process of fattening should never be 
allowed to become very hungry; because, at that moment, 
the blood begins to abstract food from the adipose tissue. 
This loss must be supplied by extra feeding. If man were 
as prudent in the selection of his food as the lower orders of 
animals are, there would be fewer lean, sickly-looking faces 
seen around us. Governed by that instinct with which their 
Creator has endowed them, brute animals select first those 
kinds of food which are most wholesome ; and if these are 
abundant, the less wholesome are altogether rejected. Man, 
on the other hand, controlled more by a vitiated or morbid 
appetite, than by the high intelligence with which he has 
been created, rejects the plain cold bread, the simple well- 
roasted beef, the nicely-boiled ham, the plainly-cooked pota- 
toes and fruit; and in their stead must have his hot rolls 
and biscuit, his highly-spiced meats, his hotly-seasoned vege- 
tables, his most indigestible pastries, his custards, and cakes, 
and candies. Then it is a wonder if he is not constrained 
to take a glass of brandy, to help out his digestive powers. 
32* 



378 GLANDS — ORG AN S OF DIGESTION. 

If we were to feed our cattle as imprudently as we do our- 
selves, our farms would be but poorly stocked. 

GLANDS. 

604. These are soft, porous organs of various shapes, situ- 
ated in different parts of the animal body, '■'■ in some cases 
extremely minute, and in others large like the kidneys and 
liver. There ai-e two classes of glands — one for the modi- 
fication of the fluids which pass through them, as the mes- 
enteric and lymphatic glands (§ 610); and the other for the 
secretion of fluids which are either useful in the animal 
economy, or require to be rejected from the body;" of such 
are the liver and kidneys. The term secretion literally 
means separation ; but as here used, it denotes both separa- 
tion of fluids from the blood, and modifications, to a greater 
or less degree, during the process of separation. The first 
class of glands above mentioned do not properly secrete, but 
rather transmit fluids, under a slightly modified form. 

. ORGANS OF DIGESTION. 

605. Digestion consists \n, first, reducing the food to small 
particles, suitable to be acted on by the fluids with which it 
is mingled in the stomach and intestines ; and secondly, dis- 
solving out the nutritive portions, and preparing them to 
pass into the organs of circulation, where they form the ele- 
ments of the blood. 

The organs of digestion are the mouth, the stomach, the 
intestines, and the lacteals. These are all lined with a mem- 
branous coating, in some respects similar to the skin, and 
connected with it where both come together, as on the mar- 
gins of the lips, nostrils, &c. This lining is called the 
" mucous membrane," because it secretes a slimy fluid called 
"mucus," which keeps the digestive and other organs moist, 
and protects them against injuries. 



ORGANS OF DIGESTION. 379 

606. The office of the mouth is to masticate the food, ai;d 
mingle it with saUva. While the tongue, the palate, and 
the cheeks hold the food, and toss it from side to side, the 
teeth grind it to fragments; and, in the meantime, the sali- 
vary glands, situated in different parts of the mouth, secrete 
saliva, which first moistens the food, thus assisting the teeth 
in reducing it to the proper condition, and secondly becomcji 
incorporated with it, and, passing into the stomach, seems to 
aid in the other processes of digestion. 

Food should be pcrfdctlu clieicccl, and tliorovglily minr/Icd 
ivith saliva, before it passes into the stomach. Slow and im- 
perfect digestion (dyspepsia,) is one of the consequences of 
not giving the teeth and the salivary glands time to perform 
their offices fully. Horses and cows, when fed on concen- 
trated forms of food, such as corn or meal, are apt to swallow 
it hastily without sufficient mastication. This is easily pre- 
vented, by mixing the meal with cut hay or straw, moistened 
with water. The food is then consumed more slowly, and 
the amount of chewing and salivation greatly increased. 

607. The Stomach is a large membranous sack, situated 
in the left side of the chest. It is composed of three layers. 
(1) The external, or serous coating, is very tough and strong, 
yet more or less elastic in different animals. (2) The middle 
coating is composed of muscular fibres, arranged in two 
layers. In one of these the fibres run longitudinally, in the 
other they cross these at right angles, running circularly 
around the stomach ; thus, together forming a sort of web- 
work. (3) The inner coating is the mucous membrane, 
which is arranged in folds, forming a soft and spongy lining 
to this organ. Lying in the surface of the mucous mem- 
brane, next to the middle, or muscular coating, are a set of 
tubes opening into the stomach, for the secretion of mucus ; 
and near these, a multitude of little glands, also communi- 
cating with the inner surface. By these glands the gastric 



880 



ORGANS OF DIGESTION. 



juice (§ 209) is secreted, and passed into the cavity within, 
there to be mingled witli the masticated food. 

The tube through which the food descends from the 
mouth is called the '' oesophagus." It opens into the top of 
the stomach, towards the left side. The outlet by which the 
food passes from the stomach is at the right extremity, 
opening into the upper part of the intestines, called the 
'' duodenum." Figure 54 (from Cutter,) gives a good general 
view of a section of the human stomach. 

Fig. 54. 




Fig. 54. — The inner surface of the stomach and duodenum. 1. The lower portion 
of the oesophagus. 2. The opening through which the food is passed into the sto- 
mach, 8. The stomach. 9. The openiug through which the food passes out of the 
stomach into the duodenum, or upper portion of the small intestine. 10, 11, 14. 
The duodenum. 12, 13. Ducts through which the hile and pancreatic fluid pass 
into it. a, I, c. The three coats of the stomach. 



COS. In what are called ''ruminating" (cud-chewing) 
animals, as the cow, sheep, camel, &c., the structure of the 
stomach is peculiar and complicated. These animals live 
chiefly upon grass and herbage, which they collect with great 
rapidity where the supply is sufficient ; but while engaged in 



ORGANS OF DIGESTION 



381 



gathering their food, they do but little chewing. It is 
simply crushed and moistened sufficiently in the mouth to 
render it pliant, that it may be swallowed. The real mas- 
tication is a subsequent process, which will be presently 
described. 

The stomach of one of these animals has four apartments, 
sometimes called the " four stomachs." Fig. 55 will give a 



Fig. 55, 




general idea of one of these organs. The first division, J, is 
a large sack, called the " paunch," and serves as a sort of 
store-room, into which the supply of food is first collected, 
through the oesophagus, a, and in which it is steeped for 
some time in a watery fluid entirely different from the gastric 
juice. By the contractile force of this part of the stomach, 
a portion of the crude mass of food is pressed into the second 
apartment, c, which is small, and is lined with a set of little 
honey-comb cells. Here the fibres of food are worked up 
into a ball, and when the animal ceases to collect, and retires, 
or lies down to chew its food, this ball (cud, or quid,'; is 
thrown up into the mouth, where the teeth and saliva reduce 
it to the proper condition to be returned to another apart- 



383 o n o A N s of digestion. 

meiit of the stomach, d. The process of forming the cud 
goes on quite rapidly in c. When the masticated food 
returns to enter d, there is a membranous valve by which 
b and c are closed. This third apartment is an oblong bag, 
lined with a folded membrane, called the " many-plies." In 
it the food is compressed, and has its surplus moisture re- 
moved. From this it passes gradually into the fourth apart- 
ment (e), which is the stomach proper. Here it first meets 
with the gastric juice, and here the process of digestion proper 
first begins. 

When a cow is fed on whole grain or meal alone, it passes 
directly into the third stomach (f7), without returning to be 
subjected to a second chewing; and much of it (especially 
the whole grain,) passes through the intestines entirely 
undigested. But if meal is fed in mixture with cut hay or 
straw, a large part of it passes with the fibrous food through 
all the apartments of the stomach, is chewed with the cud, 
and is consequently better fitted for complete digestion, and 
for accomplishing its part in the nutrition of the animal 
(§ 642). 

The second stomach (c) of the camel is supplied with very 
large cells, covered with a muscular membrane, by which the 
animal can open and close these cells at pleasure. In these 
a large supply of water is laid up for use as it may be wanted. 
The animal may thus carry with it a supply sufiicient for 
many days. Thus our Creator has adapted this faithful 
beast of burden, in this, as well as many other respects, to 
the important purpose which it serves in countries where 
large sandy deserts abound. 

609. The Intestines (bowels) form what is called the " ali- 
mentary canal," so called because here the nutritious portions 
of the food are separated from the refuse part. There are 
two general divisions of the intestines — the small intestines, 
and the colon. The small intestines are subdivided into 



ORGANS OF Dir, ESTION. 



583 



(1) the duodenum, which is the part into which the food 
first passes from the stomach. Into it the ducts from the 
liver and pancreas open, and discharge the bile and pancre- 
atic fluid. It extends from the stomach across to the right 
side of the abdomen, beneath the liver (Fig. 56) j thence it 




Fig. 56.— 1,1. The duodenum, 2,2. The small intestine. 3. The junction of the 
pmall intestine with the colon. 4. The appendix vermiformis. 5. The coecum. 6. 
The ascending colon. 7. The transverse colon. 8. The descending colon. 9. The 
sigmoid flexure of the colon. 10. The rectum. 



descends to the lower part of the abdomen, where it becomes 
of a pinkish color, and is then called (2) the, jrjmmm. The 
remaining part of the small intestines is (3) the ileum, which 
is of different lengths in different animals, and is coiled up 
in the middle part of the abdomen. The colon is the large 
part of the intestines. It is connected with the small intes- 



384 O R O A N S OF DIGESTION. 

tine near the bottom of the abdomen, on the right side, 
■whence it ascends as high as the lower part of the stomach ; 
then passing across in front of the duodenum to the left side, 
it again descends to the lower part of the body, where it is 
connected with the rectum (10). 

The structure of the intestines is so much like that of the 
stomach in its general features, that a definite description of 
its different layers will be unnecessary. The mucous mem- 
brane, which lines every part of it, lies in folds, so that the 
food passes readily over them, as it is transferred from point 
to point along the alimentary canal, by the muscular action 
of the intestines. 

610. There are numerous little tubes opening into the 
intestines, through which that part of the food which has 
been prepared for the formation of new blood, is absorbed 
and carried into the organs of circulation. These little ves- 
sels are called "lacteals" (lac, milk), from the milky appear- 
ance of the fluid which they absorb from the bowels. They 
pass through a set of organs called mesenteric glands, and 
at each successive gland the mimhcr of lacteals is diminished, 
while the size is increased. They at length terminate in a 
larger vessel, called the "thoracic duct." In Fig. 57, a, «, 
is a portion of the smaller intestine ; h, h, h, are lacteals ; 
»!, m, 7n, are mesenteric glands; (/, d, the thoracic duct, 
which conveys the new blood, called "chyle," to the veins. 
The lacteals and thoracic duct may be regarded as connect- 
ing links between the digesting and the circulating organs. 
In the figure, s, s, is the spinal column. 

Gil. Functions of the Digestive Organs. — When 
the food reaches the stomach, properly masticated and mixed 
with saliva, the glands which supply the gastric juice are 
stimulated to secrete that fluid freely — the muscular coat 
of the stomach is at the same time excited to activity, and, 
by its contractions and expansions, the food is kept in mo- 



ORGANS OF DIGESTION. 



385 



tion, until it becomes thorouglily mingled with the gastric 
juice. The proteine or albuminous portions of the food are 
thus first coagulated, then dissolved (§ 209), while the oily 



Fig. bt. 




matter, starch, and other portions are reduced to minute 
particles, but not changed chemically. When the food has 
been thus acted upon by the stomach and gastric juice, it 



C86 O K O A N S OF DIGESTION. 

forms a gray, serai-fluid mass called "chyme." It is then 
passed into the duodenum, where it meets with the pan- 
creatic fluid (§ 210) and the hile. These are mingled with 
it, and at once dissolve the starch, converting it into dex- 
trine and sugar, and so far dissolve the oily portions of the 
chyme, as to cause them to give a milky appearance to the 
solution, forming an emulsion. In this condition the food 
is called '' chyle." It then consists of the milky portion, to 
be converted into blood, and the indigestible part, to be car- 
ried off through the intestines. As the chyle passes along 
the intestinal canal, the milky portion is absorbed by the 
lacteals, and, after passing through the mesenteric glands, is 
thrown into the thoracic duct, and by it carried up near the 
spine to the lower jjart of the neck, where it is discharged 
into a large vein, and mingled with the blood. Fig. 58 will 
enable the reader to trace out the course of the food through 
the whole process of digestion. is the oesophagus, through 
which the food enters the stomach ; s, where it is mingled 
with the gastric fluid, and converted into chyme. It next 
enters the duodenum, d^ where it meets and mingles with 
the pancreatic fluid and bile, and becomes changed into 
cliyle. Thence it passes along the smaller intestines, /, /, i, 
where it comes in contact with the open mouths of the lac- 
teal tubes, Z, I, by which it is carried through the mesenteric 
glands, and being there slightly modified, is discharged into 
the thoracic duct, ^, t, and by it conveyed up to a point near 
the neck, where it is poured into the large vein, v, and be- 
comes a portion of the blood. 

Every farmer may soon make himself f imiliar with all the 
organs of domestic animals, by close observation, whenever 
he has an opportunity. 



OEOANS OF DIGESTION. 



387 



Fig. 58. 




388 



ORGANS OF CIRCULATION. 



ORGANS OP CIRCULATION. 

612. Having traced the nutritious part of the food through 
the process of digestion, by which it is prepared to pass as 
a portion of the blood through another set of organs, we 
must now follow it still further, and see how it is affected in 
this new channel. In order to understand the changes 
which take place during the circulation of the blood, we 
must first know something about the organs through which 
this circulation is carried on. These organs are the heart, 
the arteries, the veins, and the caj^illaries. 

613. The heart is a sti'ong muscular organ, situated in the 
left side of the chest. The general outline of its form, in 



Fig. 5'J. 




most animals, is that of a cone, having its base turned toward 
the head. It is hollow, having the cavity within divided 
into four apartments, two on each side. It may, in fact, be 
regarded as a double organ, with its two parts separated by 
a strong membrane. Each of these parts has two cavities, 



ORGANS OF CIRCULATION. 389 

one for receiving and one for throwing out the blood. Those 
which receive the blood are called " auricles/' and those 
■which send it off again are called "ventricles." The two 
cavities which lie next to the right side are called the " right 
auricle " and " right ventricle ; " those on the left side the 
" left auricle" and ''left ventricle." Fig. 59 will give some 
idea of the general structure of the human heart. Conceive 
the front of the heart to be turned towards u.s, and a verti- 
cal section to be formed by cutting in front of the middle 
of it. Then a, on the left of the figure, will be the right 
auricle, and v the right ventricle ; a' and v' will be the left 
auricle and ventricle respectively. Between the cavities on 
each side are openings (h, h) extending through conical bag- 
like valves (c, c, c), which open towards the ventricles, allow- 
ing the blood to flow in that direction ; but when any pres- 
sure is exerted, tending to drive it back into the auricle, 
these valves at once close, and resist its passage in that 
direction. On the right side there are three of these valves; 
on the left only two. They differ slightly in structure, bjit 
we shall not stop to consider that point. It will be seen, 
from the structure of the heart, that the blood can flow in 
only one direction through cither side of it; that is, from 
the auricle to the ventricle. 

614. The muscular walls which surround the cavities of 
the heart have the property of contracting and again relax- 
ing, so as to cUmiiiish and enlarge the cavity alternately. 
And this operation goes on in such order, that, when an 
auricle is contracted, the corresponding ventricle is enlarged. 
All the veins from parts of the body below the heart, meet 
in one common vein ((7), while those from above meet in 
another (d') ; and these discharge the blood flowing from the 
veins, into the right auricle. Where they arc connected with 
this auricle, there are valves, opening towards the heart, and 
allowing blood to flow in that direction, but resisting its pas- 
33* 



390 ORGANS OF CIRCULATION. 

sage back again towards the veins. When the right auricle, 
then, is enlarged, the blood from the veins flows freely into 
it; when it again contracts, the pressure closes the valves of 
the veins, but opens those of the ventricle ; and at the same 
moment the ventricle is relaxed, and allows the blood to flow 
into it. The moment it is full, it contracts and drives the 
blood out through the pulmonary artery (c), whose branches 
(e', c') lead to the lungs. The arrows show the direction of 
the current. 

As the blood returns from the lungs through the pulmo- 
nary veins (/, /,) the stream flows into the left auricle (a). 
When this is filled, it contracts ; the valves at the extremi- 
ties of /, yj are closed, preventing the current from return- 
ing towards the lungs, while the ventricle (/) is open to 
receive it. As soon as v' is thus filled, it contracts, and 
drives the blood out through the large artery (</), the 
branches of which convey it off" towards the different parts 
of the body. 

. 615. The arteries are strong cylindrical tubes, which con- 
vey the blood from the heart to every portion of the body. 
They consist of three coats; the outer one firm and tough, 
the middle one fibrous and elastic, the inner one thin and 
very smooth. The first gives them strength, and prevents 
injuries; the second permits expansion and contraction of 
the internal cavity ; the third aff"ords a smooth channel for 
the flowing stream. 

616. There are valves at various points in the arteries, all 
opening out froDi the heart, allowing the blood to flow only 
in that direction. The divisions and sub-divisions of the 
arteries arc almost innumerable, running to every point of 
every organ throughout the whole body. Besides these 
branches, there are numerous cross-connections, which mul- 
tiply as the branches increase in number and diminish in 
- size, the whole forming a sort of net-work. This is a most 



ORGANS OP CIRCULATION. 



591 



wise provision to prevent obstructions of the current, as it 
flows towards any point of the body. Let a (Fig. 60), repre- 



FiG. 60. 




sent an artery, with its branches and cross-connections. If 
the portion of the current flowing from h to h meets with an 
obstruction from pressure, or any other cause, at c, instead 
of stopping, it flnds a cross-channel, and turns aside towards 
d ; meanwhile, h gets its supply from a branch below c, by 
another cross-channel coming up from e. Without these 
connecting arteries between the continuous branches, there 
would often be interruptions in the circulation towards some 
parts of the body. 

The arteries are chiefly imbedded beneath the muscles and 
tendons, and, in exposed parts of the body, lie close to the 
bones. Here we have another display of the wisdom and 
skill of the Divine Builder of the animal structure. The 
arteries having their valves opening from the heart, allow 
the blood to flow freely in that direction ; hence, if an artery 
is ruptured or severed, the blood gushes from the opening 
with all that force given to it by the heart in driving it to- 
wards the extremities. These organs, therefore, require pro- 
tection. 

617. Veins are the tubes through which the blood flows 
back from every part of the body to the auricles of the heart. 
They also convey the waste matter from all the difierent 
points at which they meet the extremities of the arteries. 



392 ORGANS OF CIRCULATION. 

This refuse matter consists of such particles as have served 
the purjjose for which they were designed, have become worn 
out, lost their vitality, and are now taken up and thrown into 
the veins by a set of absorbent vessels, called " lymphatics," 
situated at the extremities of the minute branches of the 
veins ; besides this, the blood of the veins is charged with 
carbonic acid gas, to be conveyed to the lungs, and there 
discharged. These additions to the blood, after it leaves the 
arteries, make a larger channel now necessary. The veins 
are therefore made more capacious than the arteries. 

The veins are provided with valves opening towards the 
heart, allowing an easy flow in that direction, but resisting 
motion the other way. Hence the blood in these can only 
flow toward, and not from the heart. If, then, a vein is cut, 
there is no outlet formed directly from the heart. The blood 
must flow to the minute extremities of the arteries j and 
there, passing through little tubes, called " capillaries," into 
the veins, run on till it reaches the opening by which it 
comes to the surface. But, as the veins have none of that 
strong pressure upon them which the pulsations of the heart 
exert upon the arteries, a very slight bandage is usually suf- 
ficient to close an orifice, and cause the stream to pass on in 
its proper course. 

618. The capillaries are very minute tubes, or vessels, 
connected at one end with the extremities of the arteries, 
and at the other with the origins of the veins. They thus 
form a sort of connecting link between these two channels 
of the blood. The capillaries are too small to be seen with- 
out the aid of the microscope ; and are so numerous, that 
the point of a needle cannot be inserted into the flesh any- 
where, so as to avoid wounding some of them. They are 
found at every point in the body — in the skin, the bones, 
the muscles, the digestive organs ; in the coats of the veins 



ORGANS OF RESPIRATION. 893 

and arteries themselves, and, in short, wherever growth takes 
phice. 

The office of these little vessels is to elahorate the elements 
of nutrition brought from the digestive organs. .Those be- 
longing to any particular part of the body have the power of 
taking from the arterial blood just the kind of matter re- 
quired by that part, and of giving it the proper form. Those, 
for example, situated in the bones, have the power of secre- 
ting and depositing phosphate of lime, cai-tilage, etc., while 
those in the muscles secrete only such material as is suited 
to the nourishment of these organs ; and so of those in every 
other place. If the capillaries are in a healthy condition, 
and the blood is supplied with the proper variety of food, 
they secrete with unerring certainty the kind of matter 
wanted, and in exactly the right form and quantity for the 
situation they occupy. 

ORGANS OP RESPIRATION. 

619. The hreafliing organs are the icindptpe (trachea), 
and its branches, called " bronchial tubes," and the lungs. 

The trachea, or windpipe, passes down in the front part 
of the neck into the chest, where it separates into two 
branches, called " bronchia," which pass to the lungs on the 
right and left. These branches are each again subdivided 
into numerous smaller branches running to every part of the 
lungs, and ending in little air-cells (see Fig. 61). They 
convey the air from the mouth to the lungs in its pure con- 
dition, and bring it back deprived of a part of its oxygen, 
and charged with carbonic gas and watery vapor from the 
blood. 

620. These, like the digestive organs, are lined with mu- 
cous membrane. When this membrane becomes temporarily 
inflamed, it constitutes a "cold," and generally causes hoarse- 



S94 ORGANS OF R E S r I R A T I O N . 

ncss of voice aud coughing. When it becomes more gene- 
rally and permanently diseased, it becomes " bronchitis." 

621. The lungs are two large, spongy organs, situated on 
the right and left of the chest. They are formed (1) of the 
air-cells at the extremities of the bronchial tubes, surrounded 
by the tissue which separates them from one another; (2) of 
a net-work of capillary tubes surrounding these cells, and in 
contact with their lining membrane; then (3) the whole 
mass of the organ is pervaded in every part by arteries, 
which bring the impure venous blood from the right ventri- 
cle of the heart, and pour it into the capillaries to be oxidized 
through the porous membrane, which separates them from 
the air-cells. It is also pervaded by a corresponding number 
of veins, which receive from these capillaries the blood 
charged with oxygen, and convt-y it back to the left auricle 
of the heart. 

622. The lungs and heart are separated from the digestive 
organs by a strong membrane, extending entirely across the 
body, and attached to the inner lining of the ribs. This is 
called the " diaphragm," and helps to sustain the lungs. The 
ribs surround the lungs at the sides, and the sternum, or 
breast-bone, in front. The ribs and breast-bone are provided 
with a set of external muscles by which they are drawn up- 
ward and outward, so as to enlarge the chest. This tends to 
produce a vacuum around the lungs, by removing external 
pressure. Then the pressure of the atmosphere from with- 
out causes a current of air towards the lungs, through the 
windpipe, filling and expanding the air-cells and tubes. 
When the muscles of the ribs and sternum ai'e relaxed, these 
bones again return to their natural position, exerting at the 
same time so much pi-essure upon the lungs, as to force out 
again the air which had just entered. This motion of the 
ribs is also accompanied by an upward and downward motion 
of the diaphragm, which aids in the inhalation and exhala- 



O U ( ; A N S OF RESPIRATION. 



^95 



tion of air. Thus the process of hreathtmj is kept up by 
muscular force, which is involuntarily exerted upon the walls 
suiTounding the chest. 

623. Each of the lungs is sub-divided into lobes. Of 
these the right lung has three, while the left has but tico. 
The right lung is much larger than the left; this difference 
seeming to have been designed to make room on that side 
for the heart. 

624. It will be interesting to trace a little more definitely 
the circulation of the blood through the lungs, with the aid 

Fig. 61. 




of a figured illustration. Fig. 61 gives an ideal section of 
the heart, the lungs, and the several vessels by which the 



396 OROANS OF RESPIRATION. 

IjIooJ and air are brought together. The auricles and ven- 
tricles are here represented as in Fig. 59. Leading from the 
right ventricle is the pulmonary artery (|;, j)j P)j branching 
off, first into two large divisions leading to the two lungs, 
and then into innumerable subdivisions leading to the capil- 
laries around the air-cells (c, c, c). The pulmonary arteries 
are represented by dark-colored lines, because the blood they 
convey is the impure, dark-colored blood, brought from 
various parts of the body by the general system of veins. 
The pulmonary veins {q, q, q,) convey the lighter, oxygenated 
blood back to the heart, and pour it into the left auricle. 
The trachea and bronchial tubes {t, t, t,) convey the air into 
the cells, where it is separated from the blood only by a very 
thin membrane, which has such a structure as to allow gases 
and water to pass through it readily, but resists the passage 
of the blood. 

625. Summary. — If we could watch the blood of an 
animal from the moment the chyle is thrown into it by the 
thoracic duct (§ 611), until it returns again to the same 
point, we should observe some most remarkable and inte- 
resting phenomena. It has been seen by physiologists at 
every point in its circulation, and its various changes most 
minutely examined with the help of the microscope. Let us 
follow it. 

As the dark current flows past the mouth of the thoracic 
duct, the new elements of nutrition mingle with it, and all 
are received by the right auricle of the heart. Here it 
undergoes no change, but passes directly into the right ven- 
tricle, from which it is driven along the pulmonary artery 
(still dark in color), into the lungs, where the capillaries 
spread it over the outer surface of the air-cells. So soon as 
it comes in contact with the membrane which surrounds 
these cells, and which has one side exposed to the air, its 
carbonic gas, and a portion of its water, are rapidly trans- 



ORGANS or RESPIRATION. 397 

mitted into the air-cells, while oxygen is transmitted with 
equal rapidity from them in the opposite direction, and ab- 
sorbed by the blood. So the breath returns from the lungs 
charged with carbonic acid and watery vapor, while the blood 
returns towards the heart chai-ged with oxygen. 

626. Pure air and freedom of motion are both essential to 
the healthful action of the lungs. Unwholesome gases not 
unfrequently find their way to the blood through the air-cells 
of these organs during respiration. A large number of animals, 
confined in a close room, soon vitiate the air with the car- 
bonic acid of their breath, to such an extent as to cause 
death (§ 63). If the lungs are confined by external pressure, 
from tight clothing, or any kind of tight bandage, they are 
unable to expand sufficiently to inhale the requisite quantity 
of air. Hence the blood is not properly oxydized, and con- 
sequent injury to health follows. 

The most marked change which is found to have taken 
place in the blood, while passing through the lungs, is its 
change of color, resulting from the absorption of oxygen gas. 
The color is now a bright crimson. In this condition we 
find it passing into the left auricle of the heart; thence it is 
driven into the left ventricle, from which it is forced out to 
every part of the body, through the arteries into the capilla- 
ries. Here we find it performing the important office of 
nutrition. With the help of the oxygen brought from the 
lungs, its proteine constituents undergo those slight modifi- 
cations, which adapt them in one case to building up the 
skin, in another to building up the muscle, in others the 
various forms of tissue. In the bones we find it leaving 
some of its proteine matter in the form of cartilage, and its 
phosphate and carbonate of lime, as the hard minerals of the 
animal frame-work. The oily portions of the food are depo- 
sited in tlie adipose tissue. Thus the nutrifioiis portions of 
the blood are disposed of 
34 



398 . ORGANS OF RESPIRATION. 

If now we observe the starch, sugar, and gum, we find 
them disposed of in a different way. As they pass through 
the capillaries they are rapidly consumed. The greater part 
of the oxygen from the lungs combines with their carbon, 
forming carbonic acid, and generating heat in every part of 
the body, while their hydrogen and oxygen are liberated in 
the form of water. Here we find combustion going on, 
similar to that which takes place in the open air when wood 
is burnt (§ 65), and ainmal heat thus constantly kept up. 
These products of combustion (carbonic acid and water,) now 
pass into the veins, and are carried to the lungs. 

627. From every point to which the blood has carried 
fresh nutriment, we see it conveying away the old, worn out 
material, that has performed its full service. This is now to 
be discharged through various organs constructed for that 
purpose. We have already seen the carbonic acid, and a 
portion of water thrown out through the lungs. Other sub- 
stances, in the form of excretions, disappear at various other 
points. The decomposed proteine substances are separated 
from the blood, chiefly by the kidneys, and are discharged 
as a part of the urine. Several mineral salts are also thrown 
out at the same time (§ 215), and with these a large quantity 
of water. Through the pores of the skin, water, some salts, 
and organic matter, are discharged as perspii'ation. The 
skin also carries on the process of respiration to some extent 
— absorbing oxygen, and exhaling carbonic acid, but only on 
a limited scale. 

These various processes are not completed to their full 
extent, during any one round of circulation. For example, 
the blood cannot all pass through the kidneys at every round, 
to discharge its urinary matter; nor can it all reach the skin, 
to throw olF at once what belongs to the perspiration. But 
in the numerous and rapid circuits it makes day after day. 



ORGANS OF RESPIRATION. 399 

all the matter it holds, whether for nutrition or excretion, 
finds its destined place. 

628. Water, Sugar, Alcohol, &c. — Sluch of the water taken 
into the stomach is rapidly taken up by the absorbent vessels 
of the coats of the digestive organs, and thrown at once into 
the blood, without passing with the chyle through the tho- 
racic duct. An immediate effect of this is seen in the 
increase of perspiration, produced on a warm day, by a free 
draught of water. " The sugar contained in the food, or 
formed from the starch, appears to be in great part absorbed 
by the coats of the stomach and small intestines, in the same 
way as water and saline fluids, and thus finds its way into 
the veins without passing through the chyle-duct. It is 
directly oxydized in the circulation, and in a few hours after 
its ingestion disappears entirely from the blood. Alcohol is 
absorbed in the same way, and oxydized in the circulation, 
being converted into water and carbonic acid." — {Silliman, 
Jr.) Hence, if food and alcohol be taken into the stomach 
at the same time, the alcohol will reach the brain through 
the blood, and produce intoxication, long before the food 
has passed out of the stomach. The oxydation of alcohol in 
the blood produces large quantities of carbonic acid and 
water, and this combustion, which goes on rapidly, gives rise 
to an unnatural degree of heat. 

629. Respiration of Plants and Animals. — The 
effect of the combined influence of the breathing processes 
in animals and plants on the condition of the atmosphere, 
has been mentioned (§§ 65, 625). These two classes of or- 
ganic beings exert a remarkable compensating influence, in 
preserving the proper proportions of oxygen and carbonic 
acid in the atmosphere. In the structure and arrangement 
of an " Aquarium," we have another beautiful and instruc- 
tive example of a similar compensation in water. 



400 



THE AQUARIUM. 



An aquarium is properly an artificial pond, in ■wliicli aqua- 
tic plants are cultivated. It is also used as the habitation 
of fish and other water animals, kept for amusement or use. 



Fig. 62. 




Aquatic plants require the water in which they grow to be 
Bupplied constantly with a certain amount of carbonic acid, 



QUESTIONS. 401 

to be absorbed by their leaves. Fish, on the other hand, 
require a constant svipply of oxygen in the water they in- 
habit, and a constant removal of carbonic acid. Fish breathe 
the oxygen, dissolved in water, through their gills, which 
serve for them the same purpose as lungs in land animals. 
When they are confined to a small portion of water, they 
soon die, unless the water is renewed from time to time, or 
its gases in some way fitted for their respiration. 

If the object is to rear fresh-water fish, the aquarium must 
be supplied with fresh water; and, to avoid the necessity of 
changing it frequently, fresh-water plants must be cultivated 
in it, so as to absorb by their groAvth the carbonic acid and 
other impurities, and at the same time renew the exhausted 
supply of oxygen. If salt-water fish are to inhabit the aqua- 
rium, sea-water, or water of similar quality, with plants natu- 
rally adapted to it, must be provided. 

Besides the artificial pond in the garden or the lawn, the 
aquarium has of late assumed another form, and become a 
fashionable household ornament. In the form of a very 
large glass vase, like that in Fig. G2, it has found its way 
into the parlor and the hall. Here we have the little fresh 
or salt-water lake, with its rocks, its soil, its plants, and its 
finny inhabitants, all grouped in miniature, to amuse and 
instruct us. 

QUESTIONS ON CHAPTER XXVI. 
§ 580. Of what does Animal Physiology treat? Why should every 
man have some knowledge of this subject? What animal is here 
taken as the type of most perfect structure ? 

581. With what are animals generally covered? Of what two 
general divisions does the skin consist? 

582. Describe the cuticle. On what parts of the human body is 
this peculiarly thick and strong? If the cuticle is broken or re- 
moved, what is the consequence ? What are pores ? What is said 
of their number? Of what does the lower surface of the cuticle 

34* 



402 QUESTIONS. 

consist? AVhat effect do light and heat have upon this colored 
layer? How is the cuticle renewed? What are the effects of 
washing with soap ? 

583. Give the structure of the cutis vera. What are the pecu- 
liarities of its outer layer? What renders it sensitive? What are 
papillae ? Describe the inner layer of the true skin ? What glands 
are situated here? How are they connected with the hairs? What 
oflBce is performed by the perspiratory glands ? 

584. What is the adipose tissue ? Describe Fig. 49 ? 

585. What is the leading office of the skin ? How is it peculiarly 
adapted to the purposes it serves ? What is the effect of too much 
friction or pressure upon the cuticle ? 

586. What part does tlie sensitive layer perform ? 

587. What is the office of the pores ? The effect of increase of 
temperature ? What is insensible perspiration ? What experiment 
illustrates it? The effect of checking perspiration? What care is 
necessary? What precautions may be adopted for both man and 
horse ? 

588. Use of the oily secretions ? Effect of cleanliness ? 

589. For what are skins valuable ? Why? Give the chemistry 
of tanning (196). 

590. Appendages of the skin ? Of what composed (201) ? De- 
scribe a hair. Of what does wool-dyeing consist ? Are the surfaces 
of hairs smooth ? Describe fibres of wool. 

591. Use of nails, claws, and hoofs? Advantages of their per- 
petual growth ? 

592. Office of bones ? Their composition? Describe the perios 
teum. 

593. Parts of the solid mass of the bone ? Marrow ? 

594. How are the bones protected where they meet in joints? 
How is friction diminished? Describe Figs. 51 and 52? 

595. How are joints held together? How are bones connected 
where there are no joints? Example? 

596. AVhat are the chief functions of bones? Examples of bones 
protecting other organs ? 

597. AVhy are slender bones desirable ? 

598. How are the muscles situated? Their construction? How 
attached to the bones ? How do they become active ? 

599. What is the most important office of the muscles? How 



QUESTIONS. 403 

performed ? Explain Fig. 53. Why arranged in pairs ? Can the 
same muscle act perpetually? Influence of habit? 

600. Effect of too violent action ? How does change of position 
afifo I'd relief ? Illustrations? 

GOl. Character of muscles of young animals ? Effect of moderate 
exercise ? 

602. Describe the adipose (issue. Where situated? What becomes 

of the fat of animals, when not well fed ? When sick ? Influence 

of adipose tissue on form ? 

♦ 603. Why should fattening animals not be allowed to become 

hungry ? How do the lower animals select food ? How does man ? 

604. What are glands? Their size? Meaning of secretion? 

605. In what does digestion consist ? Organs of digestion ? How 
lined ? Use of mucus ? 

606. What is the oflice of the mouth? Of the salivary glands? 
To what condition should the food be reduced before passing into 
the stomach ? How may horses and cows be made to masticate meal 
properly ? 

607. How is the stomach situated? Describe its three coats? What 
is the oesophagus ? The duodenum? Describe Fig. 54. 

608. What is said of the stomachs of ruminating animals ? Illus- 
tration. What if a cow is fed on whole grain or meal alone ? Ad- 
vantage of mixing meal with cut hay or straw? What is peculiar 
about the second stomach of the camel ? 

609. What is the alimentary canal ? Why so called ? Its two 
general divisions? Subdivisions of the small intestines? Of the 
colon? Illustration. Structure of the intestines? 

610. What are the lacteals ? Thoracic duct? Explain Fig. 57. 

611. Influence of food upon the stomach? What portions of food 
are dissolved in the stomach? What is chyme? What changes take 
place in the duodenum? What is chyle? How is the chyle con- 
veyed to the blood? Object of Fig. 58? Explain it. 

612. 613. What are the organs of circulation? Describe the heart. 
What are auricles and ventricles ? Describe Fig. 59. 

614. Explain the contracting and expanding of the auricles and 
ventricles ? With which cavities of the heart are the veins con- 
nected ? With which are the arteries connected ? 

615. Describe the arteries. Uses of their several coats. 

616. How are the valves of the arteries arranged? What does 



404 QUESTIONS. 

Fig. 60 illustrate ? Why are the principal arteries placed beneath 
the muscles and tendons ? 

617. What are veins? What vessels are connected with the minute 
branches of the veins ? How are the valves in the veins constructed ? 

618. What are the capillaries? What of their size? In what 
parts of the body are they found ? Their office ? 

619. 620. What are the organs of respiration? Situation and divi- 
Bions of the windpipe? Their office? How lined? What diseases 
mentioned ? 

621. Describe the lungs. How are the arteries and veins connected 
with the lungs? 

622. How are the lungs and heart separated from the digestive 
organs? How surrounded on the sides? Howls the chest expanded 
and contracted ? 

623. Divisions of the lungs? 

624. Trace the circulation of the blood through the lungs, in 
Fig. 61. 

625. If we could watch the blood throughout its course, what 
would we observe ? What does the current receive from the thoracic 
duct? Any change in passing through the heart? What change 
in the lungs ? 

626. Influence of impure air ? Most marked change in the blood 
in passing through the lungs? Through which side of the heart 
does the blood pass after it leaves the lungs? What takes place in 
the capillaries? How are starch, sugar, and gum disposed of? 
How is animal heat kept up ? What are the products of combus- 
tion (65) ? 

627. What is carried off by the blood from different parts of the 
body? How disposed of ? Are these various processes completed 
during every round of circulation ? 

628. How is water often transmitted to the blood ? How illus- 
trated ? What of sugar and alcohol ? 

629. What is the compensating influence between plants and ani- 
mals ? What is an aquarium ? How do the plants and fish together 
preserve the purity of water ? 



SELECTION or EOOD. 4.05 



CHAPTER XXVII. 

SELECTION AND PREPARATION OF FOOD. 

630. We have learned from the last two chapters, that 
food is disposed of in several different ways : 

1. In nutrition — that is, in promoting the growth of the 
various organs, as in young animals ; in replacing the worn- 
out material of these organs, and in supplying the various 
fluids secreted in different parts of the body, among which 
we may include the inilk of female animals. 

2. In fattening — that is, in filling the adipose tissue with 
the peculiar fat of the animal under consideration. 

3. In respiration — supplying to the blood such elements 
as are oxidized, and converted at once into carbonic acid and 
water, and thus keeping up the heat of the animal system. 

631. To these several points we should give attention, in 
determining the Idnds and variety of food to be given, whe- 
ther to man or beast. There are several other circumstances 
not to be overlooked in connection with this subject, of which 
the following may be mentioned : 

(a) Whatever may be the primary object in view, whether 
to promote growth, increase strength, to produce milk, or to 
fatten, the food must have a sufficiency of starch, sugar, or 
similar compounds, to supply the demands of the respiratory 
process. Animal heat must be kept up; and if the requisite 
quantity of respiratory food is not supplied through the di- 
gestive organs, the fat will be withdrawn from the adipose 
tissue, and the animal must become lean. More heating food 
is required, too, in cold, than in warm weather. Animals 



406 SELECTION OF FOOD. 

then breathe more rapidly, in order to keep up the proper 
degree of warmth ; and if food is deficient, there is a rapid 
falling-off in their condition. Hence we find stock not so 
easily kept up in Winter as in Summer. Diflfcrence of cli- 
mate has an influence on the kind of food which the system 
demands, as we see illustrated in the case of men from our 
own country, spending a winter amongst the snow and ice of 
the Polar regions. Dr. Kane, in his " Arctic Explorations," 
says : *' There are few among us who do not relish a slice of 
raw bluhher, or a chunk of frozen walrus beef. The liver of 
a walrus, eaten with little slices of his fat, — of a verity it is 
a delicious morsel • * * * * and, as a powerful and con- 
densed heat-making and anti-scorbutic food, it has no rival." 

(Jj) The digestive organs are capable of great distention 
and contraction. If the food is very much concentrated, it 
nearly all disappears during its passage through the intes- 
tines. These organs then become so much contracted as to 
be brought to a state of constipation, which is always unfa- 
vorable to health. The stomach, too, acts with less enei'gy 
in such a case, than it does when distended by a portion of 
insoluble food. Fibrous food, in some form, is necessary for 
nearly all animals, but especially for those whose natural food 
is grass and grain, such as the horse and cow. Fine flour 
and meat, alone, do not constitute a wholesome diet for man, 
especially in warm climates, or in Summer. The bowels 
require both distention and friction from fibrous matter. 
This may be supplied by leaving the bran in flour, or by eat- 
ing vegetables and ripe fruits. A horse fed on grain alone, 
never thrives well ; he requires the addition of hay or straw. 
Some kinds of grain, like oats, have a husk, which provides 
a considerable supply of woody fibre. 

632. Food /or growing animals must be highly nutritions. 
Every part of the system has to be built up. The muscles, 
the tendons, the skin, and various membranes and fluids, 



SELECTION OF FOOD. 407 

require for their increase an abundant supply of proii^uie 
matter. The adipose tissue is to be provided with o//y sub- 
stances for forming fat. The bones, which at first are com- 
posed chiefly of organic matter (§ 204), are to be solidified 
with pliospliate of lime from the food. The fluids of the 
body all require for their perfection the soluble salts of po- 
tassa and soda. Besides all these, resjnration must be pro- 
vided for. What a variety of properties, then, must the food 
adapted to the young animal possess ! But in the sweet and 
wholesome food which God himself has provided for his 
tender creatures, we have a most perfect standard. Milk 
contains all that the wants of the young animal demand, 
until it is capable of chewing and digesting other forms of 
food. Caseine of milk is readily converted into fibrine and 
gelatine, by the digestive and circulating organs. Butter 
provides fat for the adipose tissue. The bones, too, find 
here their special mineral, as if provided in anticipation of 
their wants (§ 204). The other mineral salts necessary for 
other parts of the body, are also found here. Then the fuel 
consumed to keep up the animal heat, is furnished as lactose 
(sugar of milk). Could we find a more perfect adaptation 
of means to an end, than we have in the composition of milk ? 
As soon as the young animal is capable of taking other 
forms of nourishment, we should provide it with such as 
most nearly resemble milk in composition. Of the diff'erent 
kinds of grains, no one has a composition so nearly resem- 
bling milk as beans or peas (see Table VIII). Bean meal is, 
therefore, one of the best kinds of food for calves, colts, and 
pigs, as science would tell us, and as numerous experiments 
have proved. But to adapt it to their yet feeble digestive 
powers, it should be hoiled. Grass and clover are among 
Nature's own provisions for this same purpose. Steamed 
hay has been found to be well adapted to this kind of feed- 



40S SELECTION OF FOOD. 

iiig. Vt'Iicat-hrau mixed with a little corn meal, and boiled, 
forms an excellent food for calves and pigs. 

Goo. Milch cows require food containing an abundance of 
substances convertible into the elements of milk. Hence 
their food should not differ widely in character from that 
given to young animals. It may diiFer chiefly in being 
adapted to a dissimilar condition of the digestive organs. Food 
in a less digestible form may be given to the full-grown ani- 
mal. Such animals require more fibrous matter in their food, 
than is required by the young. Bean and pea meal, wheat- 
bran, clover and pea hay, cabbage, carrots, beets, etc., are 
good articles of food for cows. The quantity of butter may 
be somewhat increased by mixing a little corn meal with the 
cow food. If there are not enough of oily substances in the 
food to provide butter for the milk, the adipose tissue is ex- 
hausted to supply the deficiency ; hence the difficulty of 
keeping animals fat while giving milk. 

634. Strength is required, especially in those animals em- 
ployed in labor. The strength and activity of an animal 
reside chiefly in the muscles ; it is hence of the highest im- 
portance to have these organs well developed and well sus- 
tained. It has been shown (§ 600) that the muscles are 
exhausted by long-continued exercise. If the increase of 
waste thus produced is not provided for by proper food, ex- 
haustion and weakness must be the result. Such animals, 
then, should have food containing an abundance of nutritive 
matter. 

635. Exercise, and consequent waste of the muscles, ren- 
der more abundant supplies of nutrition from the blood 
necessary; and, in order to meet this necessity, the increased 
activity has the eft'ect of making the circulation of blood 
more rapid. The rapid circulation demands rapid and free 
respiration, and thus increases the consumption of respiratory 
food. This must be supplied through the digestive organs, 



SELECTION OF FOOD. 409 

else the fat from the adipose tissue will be demanded to meet 
the deficiency, and the horse or ox will become " poor." 

G36. Hence, a proper combination of nutritive and respi- 
ratory elements must be contained in food, to adapt it to the 
wants of animals subjected to severe exercise. But whilst 
the muscles of one part of the body are actively employed, 
those in other parts are often subject to a corresponding in- 
activity ; hence the muscles of the digestive organs are less 
active, at the moment action is going on in other parts of 
the body, than they are while the body is at rest. In the 
mean time, the fluids from these organs have been rapidly 
absorbed and carried to the blood. Especially is this the 
case in the intestines. A frequent consequence of this is 
constipation of the bowels, from more than ordinary exercise. 
After the exercise has ceased, or while it is suspended, the 
digestive process is restored with increased rapidity; but the 
bowels have meantime, probably, become too much contracted 
for their activity to be soon restored, and inflammation and 
diarrhoea are often the result. To guard against this evil, a 
considerable quantity of insoluble fibrous matter should be 
mingled with the food, so as to keep the digestive apparatus 
properly distended and stimulated. If the exercise is such 
as to agitate the bowels considerably, diarrhoea, instead of 
constipation, may result. 

The above principles point to a mixture of grain and hay, 
as afibrding probably the best combination of those proper- 
ties which adapt food to the use of work-animals. We find 
in these the requisite amount of proteine compounds, for 
keeping up the muscular strength ; of starch, gum, and sugar, 
for supplying fuel for respiration ; of oil, to prevent the ex- 
haustion of fat ; and of vegetable fibre, to prevent constipa- 
tion, and aid digestion. The perfection of horse provender 
is, perhaps, found in good clover or timothy hay, and corn- 
35 



410 SELECTION OF FOOD. 

meal — the hay being cut up and mixed with the meal, and 
water enough added to make the hitter adhere. 

637. An occasional change of food is promotive of health, 
provided only wholesome food be always given. The addi- 
tion of a little wheat-bran to the provender of horses, or even 
a few potatoes, beets, or pumpkins cut into fragments, and 
mixed with their usual food, improve their health by cleansing 
the mucous membrane of the intestines. The effects will 
be seen in a more soft and pliant condition of the skin, and 
in the improved, glossy appearance of the hair. 

There is a close connection and strong sympathy between 
the skin and the mucous membrane, and whatever promotes 
or impairs the health of the one, has a corresponding effect 
upon the other. Sudden changes of temperature, which 
impair or weaken the action of the skin, sometimes result in 
inflammation of the mucous membrane of the nostrils, tra- 
chea, and lungs (§ 620) ; and at other times the stomach and 
bowels become similarly diseased from the same cause. On 
the other hand, food which fails to promote healthful action 
in the mucous membrane of the digestive organs, causes fre- 
quent eruptions on the skin, or unnatural secretions in other 
parts of the body. 

638. If the object we have in view is io fatten an animal 
with the greatest possible rapidity, the chief point in which 
his food should differ from that of the growing animal, should 
be in the relative quantity of oily matter contained in it. 
While it should be adapted to sustain, and even increase, the 
muscular and membranous parts of the body, it should be 
more especially adapted to the filling up of the adipose tissue 
(§ 602). It should, therefore, contain as much oil as is con- 
sistent with healthful digestion. 

By referring to Table VIII., it will be seen that corn is 
more abundantly supplied with oily matter than any other 
of the grains commonly used in feeding. Next to it the oat 



PREPARATION OF FOOD. 411 

crop is most prominent. There are some other grains, such 
as flax-seed and rape-seed, which abound still more in oil ; 
but, as heretofore stated, they contain far too much to be 
either wholesome or palatable when fed alone ; but they are 
sometimes advantageously mixed with forms of food which 
are deficient in oil. The grasses, whether eaten green or as 
hay, have oil enough to make them highly valuable for fat- 
tening stock. The reader is referred back to § 571. 

Having selected the proper kind of food, the next import- 
ant object is to give it such preparation as will best adapt it 
to the animal by which it is to be consumed. 

PREPARATION OP FOOD. 

639. There are some important general principles involved 
in the preparation of food, which demand our attention. 
Economy in feeding requires not only the right kind of food, 
but also such preparation as will give that food its greatest 
value. It must be in such condition that the animals to be 
fed will relish it — that they will consume it entirely without 
waste — and that it shall all be digested, and thus fitted for 
the purposes it is intended to serve. We often see provender 
rejected by cattle, because its condition is that of coarse, dry, 
hard stalks, or straw, difiicult to masticate, and often insipid 
when eaten alone. Again we see the choice portions of hay 
picked out by horses, and the remainder pulled down and 
trodden under their feet. Then we often find whole grain 
passed through animals, as may be seen in the droppings of 
cattle when fed on unground corn, or of horses, when fed on 
unground oats. To avoid such waste we must give attention 
to the most economical means of reducing provender to the 
best condition. 

The means best adapted to the preparation of food are 
cutting, grinding, mixing, hoiling or steaming, and fei'- 
menting. 



412 PREPARATION OF TOOD. 

640. Cutting aids both mastication and digestion. Por- 
tions of the coarser kinds of dry provender, such as straw, 
fodder, and hay, are often rejected, as above stated, on ac- 
count of the difficulty of chewing them; and while the more 
tender parts are selected, others equally nutritious are trodden 
down and wasted. But if the whole mass is cut into small 
fragments, a great part of the difficulty of mastication is re- 
moved, and the consumption is more complete. 

In connection with the question of cutting such substances 
as straw and fodder, another question of importance arises : 
"Will it pay" to expend the necessary labor? This must 
be decided by the circumstances of the case. If the farmer 
has a great deal more straw and fodder than his stock can 
consume, and wishes to use the excess as litter for absorbing 
liquid manure, he may not find any economy in cutting. 
And even in the case of feeding hay, if the supply is abun- 
dant, and the price low, as is frequently the case in the 
grass-growing regions of Western Virginia, it may be more 
economical to feed it whole with considerable waste, than to 
expend on it the labor necessary to cut it up. But in sec- 
tions of country where such provender is scarce, or where 
there is a sufficient demand for it to keep up the price, good 
" cutters " may be among the most economical implements 
about the farm, and they are no less important in towns and 
cities where horses and cows are fed at considerable cost. 

If a farmer is near to a good market, at which he is certain 
of realizing a liberal price for his straw, hay, and fodder, his 
object should be to secure a large surplus of these articles. 
In order to do this he must feed economically at home — he 
must prepare whatever part is thrown to his farm-stock in 
such a way that it shall be entirely consumed. Then, in 
towns and cities where provender is costly, it is equally im-1 
portant to make every particle eflPective as ftir as it can be 
done. In such cases, all long forage should be well cut. 



PREPARATION OF FOOD. 413 

641. Grinding sustains very mucli the same relation to 
grain, that cutting does to long forage ; but, as grain is more 
readily transjDorted than other products of the farm, economy 
in its use becomes more generally important. Grinding is 
thought by many experienced feeders to add from 20 to 30 
per cent, to the nutritive value of grain when fed to hogs or 
horses, and from 40 to 50 per cent, when fed to cows. The 
cow masticates grain much less completely than either the 
hog or the horse. In Autumn, before corn has become hard, 
there is but little advantage in grinding for hogs. 

642. Mixing may be added to cutting and grinding with 
great advantage. When horses or cows are fed on any kind 
of long forage (hay, straw, fodder, or even shucks), together 
with meal or bran, the former should be finely cut, and the 
latter mixed with it — water enough being added to moisten 
the whole mass. There will then the double advantage arise, 
(1) of having the whole completely eaten up, without waste ; 
and (2) more perfectly masticated and digested, than if fed 
separately. A similar advantage arises from cutting beets, 
turnips, pumpkins, etc. and mixing them with meal. 

643. In localities remote from the sea-shore, where vege- 
tation affords too little of the salts of soda, to supply the 
demands of the animal fluids, common salt should be mixed 
with the food, or else a supply of it kept in a sheltered place, 
so that stock can get it when they want it. It may be con- 
veniently mingled with food, and at the same time rendered 
more acceptable to stock, by being sprinkled over hay and 
straw as they are stacked or packed away in barns. There 
is generally moisture enough present to absorb the salt com- 
pletely. From four to six quarts on a ton of hay will greatly 
improve its quality, and aid in its presentation. A small 
quantity of salt is beneficial to hogs, if given regularly; but 
large doses are very poisonous. 

644. Boiling and steaming render substances generally 
35* 



414 PREPARATION OF FOOD. 

more soluble, and in that way promote digestion. Steaming 
has been profitably applied to hay, when fed to young ani- 
mals, and to sheep, whether old or young. Green grass is 
more valuable than the hay made from it. In making hay 
there are changes produced in the stalks and blades, partly 
physical and partly chemical. Among these changes is the 
greater insolubility of the fibre. This makes it more indi- 
gestible. Steaming reduces it back to a condition somewhat 
similar to that of green grass. Boiling may be applied to 
grain, either whole or when ground. It renders the starch 
more soluble ; and if, in the case of meal, a slight fermenta- 
tion is produced before boiling, a large portion of the starch 
■will be changed to dextrine. This is one of the steps in the 
progress of digestion, already made. When whole grain has 
been boiled, it is more easily masticated, as well as more 
easily and completely digested. Hoots should generally be 
boiled or steamed. 

If our object is to make food perform its office as rapidly 
as possible — that is, if we wish it to cause rapid growth and 
rapid fattening — the most digestible condition is the best. 
In such cases, if the animals are kept comfortable and quiet, 
there is but little waste of food. Boiling is especially adapted 
to hogs, and almost indispensable to the thrifty growth of 
young pigs. 

For horses and work-oxen, the boiling of meal is a disad- 
vantage. The digestion then goes on too rapidly. If the 
grain is ground, and mixed with cut hay or straw, the diges- 
tion is made complete, but goes on more slowly. In this way 
the digestive organs are not so quickly left inactive, and 
the sensation of hunger is not so soon produced. 

G45. Fermenting meal and bran has an effect in some re- 
spects similar to that produced by boiling. Starch is changed 
to dextrine, and a portion of it even to sugar. This is a 
more economical method of preparing food than boiling, since 



PREPARATION OF FOOD. 415 

it requires no fuel, and but little labor. A very good metliod 
is to have two barrels or tubs, of sufficient size each to hold 
the material for one day's feeding. In summer, let them be 
set outside of the kitchen, in such a place that the slop may 
be conveniently thrown into them. In the morning of one 
day, have the meal for the next day's feeding thrown into 
one of the barrels, and require all the kitchen slops of that 
day to be poured upon it. By the next morning it will be 
sufficiently fermented to commence dealing it out to the hogs. 
At this time the other barrel should be supplied with meal, 
to be drenched with slop for the next day. By thus pre- 
paring in one barrel, every day, the meal for the following 
day, a supply of fermented food may be kept constantly on 
hand. During cold weather, the fermentation will not take 
place in the open air. The vessels should then be placed so 
near the kitchen fire, as to secure a temperature above 60° F. 

Care must be taken not to allow the fermentation to pro- 
gress too far. If the food becomes very sour, it contains too 
much acetic acid to be either palatable or wholesoine. To 
avoid this, the whole of the contents of the barrel should be 
fed out on the day for which it was prepared. But there is 
a limit to the quantity of slop a given number of hogs will 
drink in a day. Care must be taken, then, not to have an 
excess collected. The proper limit may soon be ascertained, 
a corresponding mark made upon the barrel. If the quan- 
tity collected is not sufficient, water must be added. Hogs 
require a good supply of liquid food (§381). 

Sugar, by a simple chemical change, may be converted 
into oily matter. The capillaries of the adipose tissue seem 
to have the power of producing this change, or at least of 
secreting more fat from the blood than was contained in the 
food, provided sugar is present. If, then, the fermentation 
is allowed to proceed just far enough to increase the quan- 
tity of sugar, without continuing long enough for this sugar 



416 QUESTIONS. 

to be converted into alcohol and acetic acid, tte fattening 
property of the food is increased. 



QUESTIONS ON CHAPTER XXVII. 

§ G30. What are the several ways in which food is disposed of? 
Explain each. 

G31. If food is deficient in respiratory substances, what is the 
consequence ? Why do animals require more of such food in cold, 
than in warm weather ? Illustration from Dr. Kane ? What cause 
of constipation is here mentioned ? How prevented ? 

632. What properties must food for growing animals possess? 
What form of food has these properties in the highest degree? AVhat 
is the composition of milic (204)? What kinds of food most resem- 
ble milk in composition ? 

G33. What kind of food do milch cows require ? Examples men- 
tioned? Why is it difficult to keep animals fat while giving milk? 

634. In what do the strength and activity of animals chiefly re- 
side ? How are the muscles exhausted ? What kind of food should 
laboring animals have ? 

635. What influence has exercise on the demand for respiratory 
food? If this is not supplied, what is the consequence? 

636. What is frequently the influence of exercise on the digestive 
organs ? How prevented ? What mixture forms the best combina- 
tion of food for work-animals ? Why ? The most perfect food for 
a horse? 

637. What are the advantages of change of food ? How are the 
effects shown ? What connection between the skin and mucous 
membrane ? Effects of sudden changes of temperature ? 

638. If we wish to fatten an animal, what should be the quality 
of the food? Which ordinary grain crop contains most oily matter? 
What of flaxseed, etc. ? The grasses ? 

639. What does economy in feeding require ? In what does pro- 
per preparation of food consist? How is the food of cattle and 
horses often wasted? Means best adapted to preparation of food? 

640. Advantages of cutting? Is cutting hay, etc., always econo- 
mical? How does convenience of market render cutting of food 
important ? 



QUESTIONS. 417 

641. What are the advantages of grinding? Why especially im- 
portant for cows ? 

642. What two purposes are served by mixing food ? 

643. When should salt be given to animals ? How may it be min- 
gled with their food ? 

644. What is said of boiling and steaming? The effect upon hay? 
Upongi-ain? Why is boiling grain or meal especially adapted to 
hogs ? Should the food of horses and worlc-oxen be boiled ? 

645. Effects of fermenting food ? What method is here recom- 
mended for hog food? Effects of too much fermentation? Into 
what may sugar be converted by the digestive process ? 



30* 



418 SELECTION AND CARE OF STOCK. 



CHAPTER XXVIII. 

SELECTION AND CARE OF STOCK. 

646. On these points we have room for only a few general 
principles, and some of their applications. For more defi- 
nite instruction, the student must resort to books which treat 
especially of these subjects. 

In the selection of stock, several important facts should 
be kept in mind. In th.e/irst place, it costs no more to rear 
or fatten an animal of the best quality, than one of inferior 
quality. But, on the contrary, it generally requires much 
less food for the best stock, than for that of inferior grade ; 
while the ultimate value of the former far surpasses that of 
the latter. Secondly, the proportion of the most valuable 
parts varies widely in animals of different structure. Any 
one may see, without very close observation, how much larger 
the bones of one beef-ox are than those of another, whose 
weight is the same. A like difference may be seen in hogs. 
ThinUi/, it must be remembered that the viuscle and \h.e fat 
determine the true value of any animal intended for slaughter. 
The hide is not to be disregarded, but is of secondary im.- 
portance. 

647. All kinds of stock whose destiny is the slaughter- 
house, should have (1) compactly-formed muscles, round and 
regular in their structure. The flesh in such cases has a 
finer texture than it has in animals with irregular, loosely- 
built muscle. (2) Their bones should be comparatively 
slender. The bone is valueless as food, but requires a large 
quantity of nutritious matter to promote its growth. (3) 



SELECTION AND CARE OF STOCK. 419 

Animals of compact structure, with slender bones, not only 
require loss food during their growth, but are more easily 
fattened than those of heavy frame and flat muscle. 

648. If strength is the object sought in our selections, it 
must be remembered that this is found chiefly in the mus- 
cles, not in the bones (§ 599). A bone of medium size, 
enveloped in well-formed muscles and tendons, is much more 
efficient than one of larger size, with muscles and tendons 
loosely constructed. But the qualities which give great 
strength are to be learned more from observation, than from 
any written description. 

649. The activity of a horse or other animal is determined 
from the structure of the bones, by the manner in which 
they are connected with one another at the joints ; by the 
general figure they give to the whole frame; then by the 
structure of the muscles and tendons, and the character of 
their connections with the bones. The bones of an active 
animal are always slender, and the joints so formed as to give 
great freedom of motion. The general form of the body is 
round, and the shoulders high. The muscles are not only 
firm, but also symmetrical in form, and so attached to the 
bones as to give the legs a tapering figure. 

650. Care op Stock. — Farmers lose as much by careless 
treatment of stock, as they do from carelessness in anything 
else. Hundreds of dollars are often lost in this way, which 
might readily have been saved by a little timely attention. 
Young animals, which require more attention than all others, 
are most frequently neglected both as to shelter and food. 
Many in this way are lost, and many others so much stunted 
as never to regain their full vigor. If, on the contrary, 
young animals are well protected against inclement weather, 
and provided with plenty of appropriate food, they soon gain 
sufficient vigor to enable them to bear the severities of Win- 
ter without danger of being lost, or of becoming so much 



420 SELECTION AND CARE OF STOCK. 

enf'jcbled as never to recover full .strength. Every farmer 
will find it to his interest to give special attention to his colts, 
calves, and pigs. 

G51. Horses. — Stables should hQ well lighted, and well 
ventilated. The eyes of horses, as well as people, are very 
much weakened by being kept in the dark ; and then, when 
brought out suddenly into the full light of day, irritation of 
those delicate organs is the result. Such treatment, often 
repeated, frequently ends in blindness. Besides securing the 
health of the eyes, light seems also to do much to promote 
the general vigor of the animal system. Pure, fresh air is 
not less important for any animal, than wholesome food. The 
lungs are capable of transmitting other gases, besides oxy- 
gen, to the blood. They are also delicate organs, and liable 
to irritation from the inhalation of impure air. If stables 
are not well aired, the horses necessarily breathe ammonia 
and other effluvia, in mixture with the confined atmosphere 
in which they live. But ventilation should be so managed 
that the horses will not be exposed to direct currents of air. 
Openings on opposite sides, higher than their heads, will 
generally give a sufficiently free circulation. These should 
be long, and not many inches deep. 

652. The temperature of stables is not to be disregarded. 
They should be neither very warm nor very cold. If they 
are very warm, the horses become severely chilled when 
brought out in cold weather. If very cold, the waste of 
animal heat requires a largely-increased consumption of respi- 
ratory food. All animals inhale air more freely in cold than 
in warm weather. This is necessary so as to increase the 
oxidation of the blood, that a more rapid combustion may go 
on in the body, and an increased quantity of heat be pro- 
duced (§ 627). The practice of making stables in the cel- 
lars of barns, is very objectionable. They are generally 



SELECTION AND CARE OF STOCK. 421 

dark, close, and too warm. If the front is made of open 
lathing, it does much to remove these objections. 

653. The use of tight girths, either in riding or working, 
confines the ribs, and thus prevents the full and free action 
of the lungs. The oxidation of the blood being thus dimi- 
nished, circulation is to some extent impeded, the injurious 
effects of which will be readily inferred from what has been 
heretofore stated. Loose girthing around the body is suffi- 
cient to keep a saddle securely in place, if a second girth is 
put around the horse's breast. 

654. Kindness does more to bring animals completely under 
the control of man, than any and all other means together; 
and, of all animals, the horse is one of the most sensitive to 
kind treatment. When colts are treated with a kind hand 
from the very commencement of life, if dealt with gently 
when first trained to the saddle or the harness, they seldom 
give their owners much trouble, and are ever afterwards 
more safe and more useful. 

655. Cattle. — Dry, clean sheds, well littered, and opening 
toward the south, make the best protection for horned cattle 
in winter. In cold, wet weather, it may be well to confine 
them to their shelters, or stable them, but generally, in fair 
weather, they do better if they have the use of an open lot, 
supplied with corn-stalks, or straw, to keep down the mud. 

When cattle are to be fattened, they should be kept as 
quiet as possible. If allowed to run at large, they take too 
much exercise, and thus cause a waste of both muscle and 
fat. They should therefore be confined to a limited area, 
but should be made entirely comfortable, so that they may 
not become restless to escape from their confinement. This 
plan, of course, cannot be pursued when cattle run on pasture 
while fattening. 

656. Hogs. — These are the most neglected of all domestic 
animals in our Southern States. Many a poor hog never 

36 



422 SELECTION AND CAUE OF STOCK. 

knows what it is to enjoy a comfortable shelter during the 
whole of his precarious life. But, when we consider the 
fact that scarcely any animal is more sensitive to extremes 
of either heat or cold, we see at once the importance of 
having him provided with comfortable shelter against the 
hot suns of summer, and the cold winds and rains of winter. 
Every farmer has observed how his hogs pant, when confined 
in the hot sun ; and how they shiver, when exposed to cold, 
bleak winds, and driving rains and snows. 

Under all circumstances, hogs should have a dry bed, fre- 
quently provided with fresh, clean litter, in cold weather. 
If they are confined to a pen in summer, the best bed they 
can have is a clean, dry floor of plank. Their bedding has 
much to do with the healthful condition of their skin, and 
consequently with the health of the animals themselves. 

657. Sheep. — The quantity of wool produced by sheep 
depends very much upon the care and attention they receive. 
Open sheds, facing the south, are the most suitable shelters 
for them in winter. Regular feeding generally finds its re- 
ward in the increased weight of both fleece and mutton. 

658. Bad habits. — The most troublesome of these is the 
habit of jumping over, or breaking through fences. Such a 
habit is more easily preve?i^e(7 than cured. Bad fences are 
the cause — good fences are sometimes the cure, but always 
the preventive. If a farmer tempts his stock to commit 
depredations, by neglecting his fences and gates, he has no 
right to complain of their propensities. 

Good enclosures are economical. Almost every rickety 
fence on a farm is the cause of more loss of time and crops, 
in a few years, than would renew or repair it many times. 
If your fences are always kept in good order, your stock 
will never learn that it is possible to break into the corn or 
wheat fields. 



QUESTIONS. 423 

QUESTIONS ON CHAPTER XXVIII. 

§ 646. What is the first reason given to show the importance of 
selecting the best quality of stock ? Second reason ? Third reason ? 

647. What qualities should be possessed by all kinds of stock in- 
tended for the slaughter-house ? 

648, 649. In selecting animals for strength, what should be espe- 
cially observed? What determines the activity of an animal? 

650. What is said of loss from careless treatment of stock? At what 
period of life do animals require special care ? 

651. How should stables be constructed? Why well lighted? 
Why well ventilated ? 

652. How should the temperature of stables be regulated? Why? 
What objection to stables in cellars of barns? 

653. Effects of tight girths? 

654. Advantages of kindness ? How may horses be easily broken ? 

655. What kind of sheds should be provided for cattle? AVhy 
should they be kept quiet while fattening? 

656. Which of our domestic animals are most neglected? Why do 
hogs require care at all seasons ? 

657. What is said of the care of sheep? 

658. Why are good fences and good gates economical ? 



424 CONCLUDING WORDS. 



CONCLUDING WORDS. 

In all parts of the brief outline here given, the author 
has aimed to be as concise as was consistent with clearness. 
Much that has been said was intended as merely suggestive. 
The leading design has been to present the great principles 
of Science closely connected with Agriculture, and to show 
how those principles are involved in the daily business of 
the farm. 

It is hoped that the young farmer will find some things so 
presented to his mind, as to inspire him with new ardor in 
his honorable profession ; and, at the same time, enable him 
to pursue it with unwonted pleasure. No profession can 
ever give much mental pleasure or satisfaction to the man 
engaged in it, unless he has, first, a clear view of the prin- 
ciples which form the basis of his operations ; and, secondly, 
a distinct understanding of the relation between these prin- 
ciples and his own practice. 

The life of the agriculturalist, as well as that of men in 
other pursuits, may have its toils, its trials, its perplexities, 
and its disappointments ; but it has, at the same time, rare 
sources of pleasure and comfort. In the first place, it is the 
most independent of all departments of industry. It is true 
there is a mutual dependence pervading all the classes of 
society, but none have to rely so little upon the capricious 
patronage of their fellow-men as the successful cultivators 
of the soil. Hence, they are less seldom tempted to resort 
to trickery and deception, than men in some other profes- 
sions, in order to secure the favorable consideration of " the 
public." 



CONCLUDING WORDS. 425 

Again, every farmer may feel that he is a member of that 
class upon whom a country like ours is chiefly dependent for 
its wealth and prosperity. The farming interests lie at the 
foundation of our national greatness. A paralysis in this 
department would evidently result in a paralysis of every 
industrial and commercial pursuit throughout this broad 
land. The farmers nourish and enrich the nation. 

The land-holders of our country, too, are the conservators 
of the purest patriotism. They are always the most stable 
and reliable citizens of this, and every other land. No other 
class of the people have their interests so closely and com- 
pletely identified with the general and permanent interests 
of every part of the country — none can be more warmly 
attached to their native soil — and none are found more 
ready at all times to raise the strong arm of resistance against 
every invasion of rights, from whatever source it may come ; 
and yet, no class of our citizens are so conciliatory and con- 
servative in all times of great political excitement. Such 
considerations give a dignity and importance to agricultural 
pursuits which few other professions can claim. 

Besides these more general relations of the farmer to 
society, which should cause him to feel no ordinary degree 
of satisfaction in the pursuit of his honorable calling, he has 
around him the more closely-associated interests of his own 
little " republic " at home, in which he can ever find much 
to alleviate any vexations which may arise to mar his comfort 
A well-tilled farm, with its appurtenances all skilfully ar- 
ranged, and in good order — with its close, strong fences, its 
deeply-plowed fields, and its well-selected, well-fed, and 
comfortably-sheltered stock — presents to the mind of any 
man of taste, a most pleasing object of regard. How much, 
then, must that pleasure be heightened, when he can say : 
"All these are my own !" If, in addition to this, the happy 
owner can look over his broad fields, and view every step 
36* 



426 CONCLUDING WORDS. 

taken in their improvement and culture, with the light of 
Science before his mind — if he can trace each effect back 
to its true cause — how much more elevated still must be his 
pleasure, and how much more complete his satisfaction ! 

There is yet a higher view, which the intelligent tiller of 
the soil may take of all that he sees around him. When he 
beholds in the light and heat of the sun, in the air he 
breathes, and in the fertilizing shower, exhaustless sources 
of life and joy — when he has learned how nicely the 
balances of Nature have been adjusted in all her depart- 
ments — his thoughts must often rise in gratitude to the 
all-wise Author of these beautiful and benevolent arrange- 
ments. In every breeze that sweeps across his fields — in 
every shower that waters the thirsty land — in the growth 
of every plant upon his soil — in every shaking leaf, and in 
every blooming flower by the wayside — Science has taught 
him to see, and seeing, to adore, the hand of Omnipotence. 



APPENDIX. 



APPARATUS AND CHEMICALS. 

The list of apparatus and chemical substances given below, ■will 
be sufficient for all the important experiments mentioned in this 
■work. They can be bought in Baltimore, Philadelphia, or New York, 
from dealers in such articles, at about the prices given in connection 
with each. 

APPARATUS. 
Beaker glasses — nest of 5, from 1 to 8 oz $0.75 

1 Bell-glass receiver — quart size 60 

Bottles — 1 thin gas generator — pint 35 

" ^ doz. wide mouths — quart 50 

Crucibles — nest Hessian 10 

Corks — 50, of assorted sizes 50 

2 Flasks, round bottoms — one 6 oz. and one 8 oz 25 

1 Funnel, glass — h pint 20 

2 Funnel tubes 30 

1 Small clay furnace , 75 

2 Stoppei-ed retorts — one half-pint and one 4 oz 76 

1 Retort stand — common iron , 1.00 

1 doz. Test-tubes — assorted sizes 50 

1 Spirit-lamp — common 50 

2 Tubes with bulb (air-thermometer) 25 

1 lb. Glass tubes — various sizes 75 

1 Thermometer — common 12 inch 1.00 

Common saucers may be used for evaporating dishes, and tea-cups 
and tumblers for various purposes. 

(427) 



428 APPENDIX. 

CHEMICALS. 

Acids — Acetic 4 oz. $0.12 

" Hydrochloric (Muriatic) 8 " .10 

" Nitric (white fuming) lib. .25 

" Oxalic 2 oz. .10 

" Sulphuric (Oil of Vitriol) 2 1b. .12 

Alcohol (common) ^ gallon, .50 

Alum I lb. .06 

Ammonia Water (Spirit of Hartshorn) J pint, .10 

Antimony, powdered 1 oz. .10 

Barium, Chloride of. 1 " .10 

Copper turnings 4 •* .25 

'« Sulphate of (Blue Vitriol) 4'- .08 

Ether, Sulphuric 4 " .20 

Fluor-spar, powdered 2 " .06 

Iodine ^ " .10 

Lead, Acetate of (Sugar of Lead) ^ lb. .10 

Litmus Paper, for testing acids 1 sheet, .06 

" Red 1 " .06 

Manganese, Black Oxide of. lib. .10 

Phosphorus 5 oz. .15 

Potassa, fused (in sticks) 1 " .12 

» . Carbonate of (Salts of Tartar) ^ lb. .15 

" Nitrate of (Saltpetre), refined ^ " .08 

" Chlorate of (for oxygen gas) ^ " .25 

«' Bitartrate (Cream of Tartar) J '* .25 

Soda, Sup. Carbonate (common) j " .05 

Zinc (granulated) 1 " .25 

Marble Powder 2 " .05 

Mercury 1 oz. .10 

Tin Foil 1 " .10 

The quantities given above will be suflBcient, if economically used, 
to repeat the experiments two or three times, in each case. Dis- 
tilled water should always be employed in dissolving chemical sub- 
stances. With a retort, and large bottle as a receiver (Fig. 7), a 
sufficient quantity of water may be distilled in a short time. The 
clay furnace, mentioned above, may be used for heating flasks and 
retorts instead of the lamp — charcoal being used as fuel. 



APPENDIX. 429 

The experimenter may soon learn to bend tubes to any shape, by 
holding them in the flame of a spirit-lamp until the glass becomes 
soft ; then, with the aid of a rat-tail file, he can easily fit them into 
corks, and thus attach them to the necks of bottles and flasks. 

TABLES. 

The following tables may often be useful to farmers for reference. 

Money. -"-The " prices current" of foreign markets are frequently 
quoted in newspapers, in accordance with foreign currencies. In 
reducing these to their value in our own coin, the tables here given 
will be convenient. 

ENGLISH MONEY. 

4 farthings make 1 penny = $0.02^'^ 

12 pence " 1 shilling = 0.24^ 

20 shillings (a sovereign) " 1 pound = 4.84 

21 shillings *' 1 guinea = 5.10 

5 shillings " 1 crown = 1.21 



FRENCH MONEY. 

1 franc equal to $0.18 

6 franc-piece " 0.93 

1 crown " 1.10 

1 Napoleon (20 francs) " 3.85 



OTHER FOREIGN MONEY. 

1 florin (Austria) cqua 

1 rupee (Bombay) 

1 thaler (Prussia) 

1 ruble (Russia) 

1 ducat (Germany) 

1 ducat (Holland) , 

1 doubloon (Mexico) 



to $0.48 
0.50 
0.73 
0.75 
2.23^ 
2.27J 
5. 53 J 



Weights. — Avoirdupois Weight is used in all business transactions. 
The old long ton of 2240 lbs. has generally passed out of use in this 
country, except at Custom Houses. 



430 



APPENDIX. 



TABLE OF AVOIRDUPOIS WEIGHTS. 

16 drams make 1 ounce (oz.) 

16 ounces " 1 pound (lb.) 

25 pounds " 1 quarter (qr.) 

4 quarters (100 lbs.) " 1 hundred (cwt,) 

20 hundred-weight (2000 lbs.) " 1 ton (T ) 

56 pounds of butter " 1 firkin. 

66 pounds of hay " 1 truss. •" 

14 pounds (an English weight).... " 1 stone. 

100 pounds of fish «' 1 quintal. 

196 pounds of flour " 1 barrel. 

200 pounds of beef or pork " 1 barrel. 

500 pounds of wheat " 1 quarter (English). 

60 pounds of wheat " 1 bushel (U. States). 

70 pounds of wheat " 1 bushel (England). 

Measures. — The standard of dry measure in the United States is 
the Winchester bushel, containing 2150j cubic inches. A circular 
vessel 18J inches in diameter, and 8 inches deep, holds a bushel. 

The English bushel now in use holds 2218j cubic inches. 

DRY MEASURE. 

2 pints make 1 quart. 

8 quarts »< 1 peck. 

4 pecks " 1 bushel. 

6 bushels of corn (South) " 1 barrel. 

8 bushels of wheat (England) " 1 quarter. 

Liquid Measure. — The wine gallon is the standard by which liquids 
are generally bought and sold. It contains 231 cubic inches. 



COMMON LIQUID MEASURE. 

4 gills make 1 pint. 

2 pints " 1 quart. 

4 quarts « 1 gallon. 

42 gallons " 1 tierce. 

31 J gallons " 1 barrel. 

63 gallons , « 1 hogshead. 



APPENDIX. 



431 



LONG MEASURE. 

12 inches make 1 foot. 

3 feet " 1 yard. 

5i yards (16^ feet) " 1 rod or pole. 

40 rods (220 yds.) " 1 furlong. 

8 furlongs (1760 yds.) «« 1 mile. 

4 inches make 1 hand. 

6 feet " 1 fathom. 

4 poles (66 feet) «' 1 chain. 

80 chains " 1 mile. 

3 miles " 1 league. 

LAND AND SQUARE MEASURE. 

144 square inches (12 X 12) make 1 square foot. 



9 square feet 

SO^ square yards. 
40 perches 

4 roods 

16 perches 

10 square chains . 
640 acres 



1 square yard. 

1 perch. 

1 rood. 

1 acre. 

1 square chain. 

1 acre. 

1 square mile. 



SOLID MEASURE. 
1728 cubic inches (12 X 12 X 12) make 1 cubic foot. 

27 cubic feet " 1 cubic yard. 

28 cubic feet (8 ft. long, 4 ft. high, and 

4 ft. wide) " 1 cord. 

24| cubic feet of stone (16 J ft. long, li 

ft. -wide, and 1 ft. high) " 1 solid perch. 



A FEW SIMPLE AND USEFUL RULES. 

I. To calculate Simple Interest, at 6 per cent. — Multiply the dollars 
by half the number of months, and the result will be the interest in 
cents. For odd days, multiply the dollars by the whole number of 
days, and divide by 60 — the result will be interest in cents. 

For any other rate of interest, as 7 or 8 per cent, multiply the 
dollars by the rate per cent — the result will be the interest for om 
year in cents. This divided by 12, is the interest for one month. The 



432 APPENDIX. 

intere."t for one month divided by 30, gives the interest for one day. 
From these, the interest for longer periods may be calculated. 

II. To determine how many Bushels a given Space will hold. — Mul- 
tiply together the length, width, and depth, measured in feel. This 
gives the contents in cubic feet. Then multiply the number of cubic 
feet by 4, and divide the product by 5 — the result will be the num- 
ber of bushels required; at least with sufficiently close approxima- 
tiou for ordinary purposes. 

Illustration. — A garner 8 feet long, 5 feet wide, and G feet deep, 

(4 X 240 \ 
p ^1 

192 bushels, very nearly. 

III. To determine the Contents of a Circular Vessel or Cistern in 
Gallons. — Multiply the diameter (measured in feet) by 3?, and this 
product by one-fourth of the diameter — this will give the area of the 
bottom, which, multiplied by the depth (in feet), gives the contents 
in cubic feet. To reduce this to gallons, multiply by 7^. (A cubic 
foot holds about 7^ gallons.) 

Illustration. — A cistern of 8 feet in diameter and 12 feet in depth, 
contains (8 X 3^ X 2 X 12 =) 002 cubic feet, and (G02 X 7^ =) 
4515 gallons, nearly. 

To determine the contents of the same cistern in bushels (see 

Rule II), multiply the cubic feet by 4, and divide by 5. Thus, 

602 X 4 

— -P— = 481? bushels. 
5 * 

If the cistern is narrower at the bottom than it is at the top, the 

diameters at top and bottom should both be measured, their lengths 

added together, and the sum divided by 2. This will give the mean 

dianieter, which may be used as in the preceding example, with a 

tolerably accurate result, provided the upper and lower diameters 

do not differ much in length ; but if they differ widely, the result 

will be too great. 



The publishers of this work will furnish the Chemicals and Apparatus given in the 
list on pages 427 and 4J8. The Cliemicals contained in suitable bottles ; the Apparatus 
of the most approved land ; and the whole carefully packed fur iransportatioji. on 
receipt of $13. 

A Galvanic Battery, capable of decomposing water, of either of the following forms, 
will be furnished asfolloxvs: — 

Bunsen's Carbon Batteries, large size $2.25 

Grm<e's Battery, 1 ceJl, $2.50; 2 cells 4.00 

MaynooVCs Iron Battery 1-75 



INDEX. 



The numbers refer to pages — App. to Appendix. 



A. PAOE 

Absorbents of Ammonia 224 

Absorption by leaves 159 

" by skin 398 

Acetates 107 

Acid, acetic 196 

" arsenious 94 

" boracic 73 

" carbonic 64 

" citric 114 

" fixes ammonia 224 

" hippuric 136 

" humic 104 

" hydrochloric 71 

" hydrosulphuric 70 

" lactic 107 

" malic 114 

" muriatic 72 

" nitric 64 

" oleic 129 

*' oxalic 113 

" phosphoric 72 

iL silicic 73 

" stearic 129 

" sulphuric 69 

" sulphurous 69 

" tannic 114 

" tartaric 113 

" uric 135 

" vegetable 113 

Acids defined 63 

Adipose tissue 376 

Affinity 25 

Agriculture defined 25 

" importance of 424 

Air^ carbonic acid in 64 

" circulation of 33 

" composition of 64 

" constant in composition.... 62 

37 



Air, dry and damp 38 

" influence of, on rocks 172 

" " " on soils 191 

" moisture in 37 

" necessary to fermentation.. 106 

" " " life 58 

Albumen, animal 126 

" desTcribed 126 

" of seeds 164 

" vegetable 108 

Alburnum of wood 155 

Alcohol, carried directly to the 

blood and brain 399 

" fermentation of 104 

Alkalies 67,77 

Alloys, metallic 95 

Alluvial soils ISO 

Alluvium ISO 

Alum 86 

Alumina 85 

Ammonia, chief source of nitro- 
gen for plant-food.. 141 

" described 66 

" expelled by lime, 67, 224 
" important in manure, 219 

" means for fixing, 68, 221 

" properties of 67 

" salts of, in organic 

matter 68 

Ammoniferous bodies 215 

" fertilizers 219 

Analysis of ashes 122,244 

" of bones 131,371 

" of guano 234 

" of soils 211 

" proximate 99 

Animal chemistry 125 

" heat 398 

" manures 235 

" physiology 363 

(433) 



4:J4 



I N I) E X . 



Animal refuse 235 

Animals, care of 419 

" feeding 405-415 

" organs of 363 

Annual plants 165 

Anther of flower 162 

Antimony 93 

Apparatus (App.) 427 

Application of manures 255 

Aquarium 4U0 

Arsenic 93 

Arterial blood 397 

Arteries, functions of 391 

" structure of 390 

Ashes, composition of 99, 120 

" of coal 246 

" of sea-weeds 244 

" of various crops 122 

" quantity in plants 120 

" Tables of 123,244 

" value of, as manure 245 

Atmosphere, composition of 64 

" influences evapora- 
tion 41 

" moisture in 37 

Atomic weights 50 

Atoms defined 60 

Auricles of the heart 3S9 

Axillary buds 322 

Azote, or Nitrogen 63 

B. 

Barium 84 

Bark described 149 

Baryta 84 

Bases defined 67 

" organic or vegetable 115 

Bathing important 369 

Battery, galvanic 44 

Beans, composition of. 301 

" cultivation of. 301 

" value of as food 355 

Bell-metal 95 

Biennial plants 165 

Bile, composition of 132 

" functions of. 386 

Blood, arterial and venous 396, 397 

" circulation of. 395-398 

" Composition of. 131 

Blue Kidge, geology of. 183 

Boiling food 413 

" influence of pressure on ;j5 

" point of liquids 35 



Bones, composition of. l.'^O 

" dissolving 236 

" experiments with 237 

" grinding 236 

" structure of 371 

" functions of. 373 

" value of 235 

Borax 73 

Botany 144 

Boulder 180 

Brain of animals 130 

Branches 156 

Bran of wheat 355 

Brass.. 95 

Bread, rising of. 80, 105 

Bronchia....?. 393 

Bronze 95 

Buds, flower and leaf. 156 

Burning fluid 110 

Burnt clay 248 

Butter 133 

C. 

Cabbage, in rotation 351 

" value of 356 

Cafeine 115 

Calcareous fertilizers 239 

" shales 183 

" soils 187 

" tufa 242 

Calcium 80 

Caloric 29 

Calyx of flowers 161 

Camphene 109 

Camphor Ill 

Caoutchouc 112 

Capillary action of soil 197 

Capillaries, functions of. 393 

" structure of. 392 

Carbon 60 

Carbonate of lime 82,175 

" magnesia 84 

" potassa 78 

Carboniferous formation 178 

Carbouicacid described 61 

140 

" sources of 62 

" quantity in air.... 140 

Care of stock 419 

Cartilage 372 

Caseine of milk 126 

" vegetable 107 

Cellular tissue 147 



INDEX, 



435 



Cellulose 100 

Chalk formation 179 

Charcoal 60 

Cheese 126 

Chemical treatment of soils 210 

Chemistry, animal 125 

" defined 25,27 

" inorganic 55 

" organic 98 

Chest, expansion and contrac- 
tion of. ."94 

Chlorine described 70 

" in plants 123 

" in soil 212 

Chlorophyll 116, 158 

Chyle 386 

Chyme 3S6 

Circulation, organs of 388 

" of blood 396 

" of sap 160 

" of air in soil 196 

" of water in soil 197 

Classification of soils 189 

Clay, an absorbent of ammonia 224 

" influence on soil 85,195 

" its composition 85 

Clay-slate 177 

Clothing 30 

Clouds, formation of 40 

" prevent dew 39 

Clover a fertilizer 218 

" cutting and curing 295 

" gathering seed of. 296 

" soil adapted to 294 

" sowing 294 

" varieties of. 293 

Coal ashes 246 

Coal formation 178 

" " soils of 185 

Colds, cause of 368 

Colon 383 

Colors of flowers 116 

Compost manures 224,258 

Compound substances defined... 26 

Conduction of heat 30 

Conglomerates 178 

Copper i 91 

Copperas, an absorbent 224 

" composition of 89 

Coral reefs, soils from 184 

Corn, composition of 356 

" cribbing 278 

" culture 272 

" harvesting 273 



Corn, planting 270 

" preparation of soil for 268 

" selection of seed 259 

" value of, as food 356 

Corolla of flowers 161 

Cotton 330 

" culture of 335 

" manuring 331, 333 

" packing 339 

" picking 338 

" planting 334 

" preparation of soil for ... 331 

" seed 338 

Cotyledon of seeds 146 

Cows, food for 408 

Cream of tartar 114 

Cretaceous formation 179 

Crops, planting and culture of, 258 

" rotation of 342 

" value of, as food 354 

Culinary paradox 35 

Cultivator, use of 200 

Curing tobacco 323 

Cuticle, structure and functions 

of 363 

Cutis vera 365 

Cutting corn 275 

" hay 295 

" tobacco 323 

" wheat 285 

D. 

Decay of organic matter 222 

Deciduous leaves 165 

Decomposition by battery 45 

Deep plowing important 196 

" " prevents drought, 197 

Detritus of rocks 187 

Devoni.in formation 173 

Dew, formation of 33 

Dextrine described 101 

" formed in digestion... 386 

Diamond 60 

Diaphragm 394 

Dicotyledonous plants 146 

Dilfusion of gases 37 

" of vapor in air 37 

Digestion, aided by condition of 

food 407 

Digestion, animal 384-386 

" in plants 160 

Digestive fluids 132 

" organs 378 

Diluvium or drift , 180 



436 



INDEX. 



Distillation 35 

" of alcohol 105 

Draining, methods of 202 

" principles of 201 

Drains, depth of 207 

" prevent drought 208 

" structure of 203 

Drift formation 180 

Drought improves soils 197 

Duodenum 383 

Duramen (red wood) "..." 155 

Drill for wheat 282 

E. 

Earth, interior condition of 175 

Ebullition 35 

Eggs, composition of. 126 

Electricity 42 

Elevation of strata I76 

Elementary substances 26 

Embryo of seeds 145 

Endogens I55 

Epidermis of pla'hts .'.".'.'." 149 

" of the skin 363 

Epsom salts 85 

Equivalents 49 

Evaporation described 37 

" influence of tempe- 
rature on 37 

Evergreens jgj 

Excrements, collection and pre" 

servation of 229 

" composition of 134 

" of horses, hogs, &c. 227 

" of man 228 

Exercise, importance of 376 

Exhalation 259 

Exogens .........' 154 

Expansion by freezing 33 

" by heat 30 



Fermentation, acetic jog 

" alcoholic 104 

" of manures 222 

_" of food 414 

Fertilizers, ammoniferous 215 

" application of. 255 

" defined 214 

" humiferous 217 

" mineral 238 

" organic 216 

" special 227 

Fibre, muscular 129 

[] woody 100,366 

" " quantity in crops, 357 

i'lbnne of blood 131 

" of muscles 125 

Fibrous roots [\\[ 151 

Filament of flowers .".'.".'.',' 162 

Filtering with charcoal '. 61 

Firing tobacco 324 

" " with charcoal 325 

Fish as manure 235 

Flame 110 

Fluids, burning hq 

" expansion of. 31 

of animals 131 



Flesh. 



129 

Flesh-fluid \['\ 130 

Fluorine ' 72 

Flower-buds .',*' i5g 

Flowers, difl'erent on different 

-.Pl'^nts 163 

J^lowers, differenton same plant 162 

" functions of. 163 

staminate and pistil- 



ate. 



163 



Faeces of animals 134 

Fallow clover 218 

" for wheat 280 

^ " pea .V.V.'.V. 307 

farmer, position of. 424 

Pat, acids of. '*'" 129 

" of animals 128 

Fattening animals 377 

" best food for .'."."; 356 

iJeldspar, described 172 



Flowers, structure of 160 

Fogs, formation of. 41 

Food, preparation of. 405,411 

" selection of. 405 

" why necessary 354,405 

" value of crops for 354 

Fowls, excrements of. 235 

Formations, geological 176 

Forms of bodies 34 

Fossiliferous rocks 176 

Fossils i7g 

Freezing, influence on rocks.... 33 

" " on soils 33 

" mixtures 34 

" of water 34 

Frost, agency in forming soils.. 181 
formation of. 181 



disintegration of, 172,182 | Fruits 'ZZZZZ 164 



INDEX. 



437 



G. 

Galvanic battery 44 

Garden rotations 352 

Gases, collection of. 50 

Gastric juice, composition of... 132 

" " functions of M85 

Gelatine described 127 

" of bones 130 

Geology defined 26, 168 

" of soils 1G8 

Geological section — Frontispiece. 

" " described 176 

Germ of plant 145 

Germination of seeds 145 

Glands of animals '. 378 

" of plants 150 

Glucose (grape-sugar) 101 

Glue 127 

Gluten 107 

Glycerine 129 

Gneiss 174 

Gold 94 

Granite, composition of. 173 

" soils from 181 

Grass, annual 299 

" culture of. 297 

Grain, ashes of. 123 

" composition of 99,354 

" grinding 379,413 

Green crops as food ». 407 

" manures 218 

" sand 179 

Guano, composition of. 135 

" effects of 233 

" history of 229 

" manipulated 241 

" modes of applying 231 

" table of varieties 231 

" testing 136,234 

Gum, composition of 102 

" in crops 355 

Gum-elastio 112 

Gunpowder 79 

Gutta percha 113 

Gypsum, application of 241 

" composition of 83 

" influence on ammonia, 224 
" with ashes 246 

H. 

Hair, composition of. 128 

" growth of 369 

" structure of 370 

Harrow, use of 200 

37* 



Hay, clover 293,357 

" composition of, (Table)... 357 

" crops for 293 

" cut for food 409 

" cutting and curing... 295,298 

" of peas 307,356 

" salting 296 

" steaming 407 

Heart, structure and functions 
of 388 

Heat, animal 405 

" influence on germination, 145 

" latent 34 

" necessary to rapid decay, 222 
" properties of 29 

Herbaceous plants 154 

Hogs, care of 421 

" manure from 228 

Hoofs of animals 128,370 

Hornblende described 174 

" influence on soils.. 174 

Horns of animals 128 

Horse, care of 368, 420 

" manure from.. 228 

Humiferous manures 217 

Humus, an absorbent of ammo- 
nia 104, 224 

Humus described 103 

" value of, in soil 140, 216 

Hydrogen, an element of orga- 
nic bodies 98 

Hydrogen, history of 58 

" properties of 59 

" sulphuretted 70 

Hypozoic rocks 117 

" " soils from 182 

I. 

Ice cream 35 

Improvement of soils 195,210 

" of stock 418 

" of quality in crops, 259 

India rubber 112 

Indigo 115 

Ink 114 

Inorganic chemistry ,... 49 

" manures 238 

" parts of plants 120 

Insects enrich soils 235 

Interior of earth 175 

Intestines, functions of 382 

" structure of 384 

Iodine 72 

Iron described 86 



438 



INDEX. 



Iron, forms of 87 

" oxides of 88 

" salts of 89 

" in blood 132 

" in plants 123 

" in soils 212 

Irrigation explained 250 

" illustrated 251 

" benefits of 252 

Isinglass 127 

J. 

Jelly of fruits 102 

" from gelatine 127 

Joints of animals 373 

L. 

Lacteals 384 

Lactic acid 107 

" " in stomach 132 

Lands to be drained 201 

Leached ashes 245 

Lead and its compounds 91 

Leaden tree 92 

Leaf-buds 156 

Leather, composition of.... 114, 369 

" tanning 127 

Leaves, structure of 157 

" functions of 159 

Legumen in food 107, 355 

Leguminous plants 301 

Lias formation 178 

Light, properties of 41 

" chemical effects of 42 

Lignine (woody fibre) 100 

Lime, as a fertilizer 239 

" carbonate of 82,240 

" phosphate of 83, 240 

" prepared 81 

" silicate of 84,242 

" sulphate of 83,241 

" superphosphate of „. 241 

" use of, on drained swamps 208 

Limestone rocks 175 

" soils 187 

Linseed oil Ill 

" cake as food 356 

Liver 378 

Logwood 116 

Lunar caustic 94 

Lungs, circulation in 396 

" diseases of. 397 

" functions of. 396 

" structure of. 394 



M. 

Magnesia described 84 

" in ashes 85 

" in lime 243 

Maize (Indian corn) 268 

Manganese 90 

" in plants 123 

" in soil 212 

Manure, application of 255 

" defined 214 

" inorganic 238 

" necessary 212 

" organic 215 

" preparation of. 227 

" special 227 

Marl as manure 242 

" described 241 

" in Tertiary strata 186 

Marrow of bones 372 

Meadows, treatment of. 200 

" watered 250 

Meal mixed with hay, etc 413 

Meat, cooking 130 

Mechanical treatment of soils... 195 

Medullary rays 154 

Membrane, animal 378 

" mucous 379 

Mercury 93 

Metalloids 55 

Metals 77 

Metamorphic rocks 178 

Mica 173 

Mica-slate 177 

Milk, ashes of 133 

" composition of. 133 

" value of. 13.3, 407 

Mineral manures 238 

" waters 60 

Minerals described 170 

Mi.xing soils 195 

" manures 258 

Morphine 115 

Mortar, chemistry of 82 

Mouth, functions of. 379 

Muscle described 374 

Mucus, secretion of. 379 

" functions of. 374 

" seat of strength 374 

" value of 376 

N, 

Negative elements 45 

Nerves 131 



INDEX. 



439 



Net-veined leaves 157 

New Red Sandstone 17S 

Nicotine described 115 

" in tobacco 324 

Nitrates as fertilizers 248 

Nitre as manure 248 

" composition of. 78 

Nitrogen described 63 

" sources of in plants... 141 
Nodules of phosphate of lime 

in Tertiary roclis 186 

Nomenclature, chemical 51 

Nutrition of animals 397,405 

" of plants 140 

Nutritive food .... 358 

0. 

Oat, culture of 286 

Oil, drying Ill 

" fixed and volatile lO'J 

" in crops 109,366 

" olive, palm, etc Ill 

" glands of the skin 365 

Old Ked Sandstone 178 

" " " soils from... 185 

Oleine 128 

Oolite rocks 178 

Ores, metallic 77 

Orchard grass 298 

Organic acids 113 

" bases 115 

" bodies 98 

" chemistry 98 

" elements 98 

" matter 98 

" matter in soil 213 

Organs of animals 363 

" of plants 149 

Origin of soils 181 

Ovary of flowers 162 

Oxygen, history of 55 

" necessary to life 58 

" properties of 56 

P. 

Pancreatic fluid 132 

Papillae 365 

Parasitic plants 152 

, Parenchyma of leaves 158 

Pasture 299 

Pea, composition of. 301 

" culture of. 304 



Pea fallow 305,340 

" fertilizing value of. 301 

" hay 307 

" Southern 302 

Peat, absorbent power of 224 

" described 103 

" value of. 219 

Peaty soils 190 

Pectine 102 

Pepsin 132 

Perennial plants 165 

Pericarp 164 

Periosteum 371 

Permean rocks 178 

Perspiration of animals 368 

" of plants 169 

Petals of flowers Ifil 

Phosphate of lime 240 

" " nodules in 

Tertiary rocks 186 

Phosphate of lime in soils 212 

Phosphoric acid described 72 

" " in plants 123 

Phosphorus 72 

Physiology, animal 363 

" vegetable 144 

Pistils of flowers 162 

Plants, annual 165 

" ashes of. 121,123 

" biennial and perennial.. 165 

" chemistry of 98 

" growth of 145 

" herbaceous and ligneous 154 

" nutrition of. 139 

" organs of. 149 

Planting corn 270 

" cotton 334 

" general principles of. 258 

" potatoes 288 

" time for 264 

" wheat 282 

Plaster as manure 240 

" with ashes 246 

Plow, importance of 196 

" sub-soil 197 

Plowing, philosophy of 196 

" down manures 223 

Plumule of germ 145 

Pollen described 162 

Pores of skin 364,367 

Potassa and its salts 78 

" in ashes 122 

" in feldspar 172 

" in soils 212 



440 



INDEX. 



Potato, composition of. 359 

" culture of 289 

" cutting 291 

" degenerating 291 

" digging 290 

" manuring 287 

" mulching 289 

" planting 288 

" preparation of soil for.. 287 
" second growing, uses... 290 

Primary rocks 177 

" " soils of. 182 

Proteine bodies as manure 219 

" " decay of 109 

" " in animals 125 

" " in plants 107 

" " value of as food 358 

Proximate constituents of plants 99 

Putrefaction 127 

" of manures 222 

" of proteine sub- 
stances 127 

Q. 

Quartz described 171 

Quinine 115 

Questions, use of. 28 

K. 

Radicle of germ 145 

Rain, formation of. 40 

Resins Ill 

Recipes for steeping seed 263 

Respiration a source of carbonic 

acid 62 

Respiration of animals 393 

" of plants 159 

" of fishes 401 

Respiratory food 358, 398, 405 

" organs 393 

Rest necessary 376 

Ribs, motion of 394 

Rice, composition of, (Table)... 357 

Ripening of fruit 102 

Rocks defined 169 

" stratified 169 

" unstratified 169 

" influence on soil 181 

Roller, use of 200 

" " " in planting to- 
bacco 319 

Roots, forms of 150 

Roots, functions of 153 

" growth of 152 

" Htructure of 152 



Rotation, division of land for... 347 

" examples of 343 

" in gardens 352 

" object of 343 

" of crops 342 

" of manures 346 

" order of 345 

Rotting of manures 222 

Rules for measuring garners, <tc. 

(App.) 432 

Rumination of animals 380 

Rust of iron 88 

Rye, composition of, (Table).... 357 

S. 

Sal-ammoniac 66 

Saline waters 60 

Saliva, composition of 132 

" secretion of. 379 

Salt, common 71 

" forstock 413 

" as a fertilizer 247 

" applied to hay 296 

Salts, Kpsom 85 

Saltpetre described 78 

'• uses of 79 

Sand, composition of 73_ 

" in soils 184~ 

Sandstone 171 

Sandy soils 189 

" " treatment of 195 

Sap, circulation of 160 

" condensed 159 

Sap-wood 155 

Scalding food 413 

Scurf on skin 365 

Sea weeds, ashes of 244 

Secretion defined 367 

Section of the earth (Frontis- 
piece) 176 

Section of pith 147 

" of oak wood 155 

Seed, cleaning 261 

" germination of 145 

" parts of 164 

" selection of 259 

" steeping 262 

Sensation distinguishes plants 

from manures 144 

Sepals of flowers 161 

Serum of blood 131 

Sheds for cattle 421 

" for manure 22S 

Sheep, care of 422 

Sheltering stock important 419 



INDEX. 



441 



Silica, forms of. 73 

" in ashes 245 

" soluble 242,245 

Silicate of lime 242 

" of soda 248 

Silurian formation 178 

" « soils of 183 

Silver 94 

" German 95 

Skin, composition of 127 

" functions of. 366 

" structure of 363 

" treatment of 369 

Slate 172 

Snow, formation and use of 40 

Soap, composition of 129 

" use of, 365 

Soapstone 171 

Soap-suds valuable 246 

Soda and its salts 79 

" in soils 80 

Soda salts as fertilizers 247 

Sodium 79 

Soil 168 

" acids in 201 

Soils, analysis of 211 

" chemical treatment of..... 210 

" classification of 189 

" clay, treatment of 195 

" cold and warm 216 

« color of 216 

" composition of 212 

" drained 208 

" fertile and barren 212 

" formation of 187 

" from different geological 

formations 181 

Soils, influence of rocks upon... 181 
" mechanical treatment of.. 195 

" organic matter in 217 

" origin of. 181 

" surface and sub-soil 188 

" varieties of. 181 

« sour 201 

Southern Pea, climate for 303 

" " gathering 307 

" " planting 304 

" " varieties 302 

Spongioles 152 

Spreading manure 221 

Stables, structure of 420 

Starch, chemistry of. 101 

Starch in crops 354 

" value as food 359 

Stamens of flowers 161 



Stacking hay 296 

Stearine 128 

Steaming food 407 

Steel 87 

Steeping seed-grain 262 

Stem, functions of. 156 

" structure of 154 

Stigma of flowers 162 

Stock, selection of. 418 

Stomach, functions of. 384 

" of man 380 

" of ruminant animals.. 381 

Stomata 158 

Stratified rocks 160 

Straw, ashes of 121 

" value as forage 406 

" value as manure 217 

Strychnine 115 

Sub-soil defined 188 

" plow 198 

Sugar, composition and varieties 101 

" fermentation of 104 

" in crops 355 

" of milk 102 

" value as food 358 

Sulphates 70 

Sulphur described 68 

" in hair and plants 69 

Sulphuretted hydrogen 70 

Sulphuric acid described 69 

" " for dissolving 

bones 236 

Sulphuric acid for "fixing" am- 
monia 224 

Sulphuric acid in soil and plants 212 

Superphosphate of lime 241 

Swamps, drained 202 

Symbols explained 49 

" use of 51 

Syenite 175 

T. 

Table of ashes from crops 123 

" of ashes used as manure. 244 

Table of crops used as food 357 

" of percentage of ashes in 
different plants 121 

Table of guano 231 

" of products of land per 
acre 360 

Table of proteins bodies 126 

" of rotation of crops 348 

" of soils 212 

" of symbols, etc 50 

" of moneys, weights, etc. 429 



U2 



INDEX, 



Talc described 171 

Tallow 128 

Tanning 114 

Tartaric acid 113 

Tassel of corn 163 

Tertiary strata 179 

Tendons of animals 374 

Therraotneter 32 

Tiles for draining 203 

Tiinl)crs used in draining 206 

Time for planting 264 

Timothy, culture of. 297 

cutting 298 

Tin described 92 

Tissue, adipose 365 

" cellular 147 

" fibrous, etc 147 

Tobacco, assorting 326 

" beds for plants 313 

" chemistry of curing... 324 

" climate 311 

" culture 320 

" cutting and curing 323 

" listing and billing 317 

" planting 318 

" preparation of soil 315 

" priming and topping.. 321 

" varieties 312 

Top-dressing 222,257 

Trachea 393 

Trap rocks, composition of 174 

" soils from 182 

Treatment of animals 421 

Trefoil (clover) 293 

Trench plowing 200 

Tuberous roots 151 

Tufa, calcareous 242 

Turpentine, spirits of 109 

Type metal 95 



Unstratified rocks 180 

Urate of ammonia 135 

Urea described 135 

Urine of animals 134 

" of birds solid 135 

" preservation of 227 

" value of. 228 

V. 

Vacuum, evaporation in 37 

Valley of Virginia, soils of 183 

Value of crops 354 

Vapor in air 37 

♦' condensation of. 38 



Vegetable chemistry , 100 

" fibre 100 

" physiology 144 

Veins of animals 391 

" of leaves 157 

Venous blood 398 

Ventilation of houses 379 

" of stables 420 

Ventricles of the heart 388 

Verdigris 91 

Vinegar, preparation of 106 

Vinous fermentation 104 

Vitality, influence of 354 

Vitriol, oil of 69 

Volatile oils 109 

" parts of manures 228 

W. 

Waste of manure 228 

Water, a fertilizer 249 

" an element of nutrition 

for plants 140 

Water, composition of 60 

" freezing of 33 

" of springs 249 

" stagnant on soils 201 

Watering meadows 250 

Weeds, sea, ashes of 244 

Weights, Tables of, (App.) 429 

Wheat, composition of 99,354 

" culture of 280 

" drilling 282 

" harvesting 285 

" manuring 281 

Wheat, planting 282 

" seed cleansed 259 

" steeping seed 262 

Wind, cause of 33 

Wood, composition of 100 

" structure of 155 

Wood-ashes 244 

Woody fibre 356 

" " in crops 356 

" " in food 406 

" " sotrrce of humus... 217 

Wool, composition of 128 

" structure of 370 

Y. 

Yeast, in bread 105 

Young animals, care of 419 

" " food for 406 



Zinc and its compounds 90 



iap'33 



Sfpt. 



rn 



